1990 rebuilt 5.7 water in oil and timing problem

stang32 said:

hey guys i need some help, i am installing a new motor and i have it mounted on a pallet on a trailer for testing purposes,
I would NOT run it for very long on a pallet. It needs to be loaded in order to begin the seating process for the piston rings.

i have the manifolds risers and elbows in place. all new exhaust (sierra) and i am getting water in my oil. could the exhaust not being atached to the y pipe be sucking the water back into the cylinders?
Unlikely that not being connected to the Y pipe would cause that. You have something else going on.

this is the 2nd time this is happened. the ist time i sent the engine back to the builder, i filled the manifolds with acetone and found no leaks, i had the intake pressure tested and no problems found.

the 2nd issue it the timing. i can not get the timing to within specs and sound right.
How are you checking the ignition advance?

this rebuilt engine has a pertronix ignition in a pretrolte dist. no weights, just a shaft set up. basic.
Any ignition system without advancing flyweights would be an EST system.

the engine sounds the best at 22deg btdc, when i bring it to 8 deg, it runs rougher, not as smooth as 22.
This is at idle?


the vacuum gauge is very bouncy, violently bouncing from 16-22i in hg.
Vacuum readings will not mean much until you get the ignition advance and the fuel delivery system set up correctly.

i have confirmed tdc with a piston stop and it lines up with the timing marks perfectly.
The PPS procedure requires the use of a degree wheel and a temporary pointer.
Was this done?

what am i missing. i have never had an issue like this before and i am stumped
the engine has already been back to the builders and they claim there is no issue what so ever with it. so how do i ecplain the vascuum gauge dance and the timing issue?
Somewhere, something is being over-looked.

if the water in the oil is caused by the manifold back pressure, whats the fix for that?

i know the truck cams have an overlap in the valves which could cause seawater to be sucked in so what to do?
Is the camshaft phased in correctly?

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stang32 said:

hey guys i need some help, i am installing a new motor and i have it mounted on a pallet on a trailer for testing purposes,
I would NOT run it for very long on a pallet. It needs to be loaded in order to begin the seating process for the piston rings.
why cant i run on the pallet? i have water runing through it and gauges all hooked up for monitiring
I did not say to NOT run it. You can safely run the engine while on the pallet and with water connected.
What I said was to NOT run it for a long duration with the intent to get some time on it.... (other than a 15/20 minute flat tappet cam follower break-in!)

Reason:
A newly built engine must be loaded in order to create cylinder pressures that cause the piston rings to seat properly against the cylinder walls.
If you run it for a long duration on the pallet, you will miss this opportunity, and there is NO going back!

i have the manifolds risers and elbows in place. all new exhaust (sierra) and i am getting water in my oil. could the exhaust not being atached to the y pipe be sucking the water back into the cylinders?
Unlikely that not being connected to the Y pipe would cause that. You have something else going on.
ageeed ,but what?
ive sent the intake out to be tested, ok, i did an acetone test on the manifolds/risers, ok
I would suggest performing a cylinder leak-down test. Not necessarily for piston rings or valves, but more so for a possible head gasket failure.

this is the 2nd time this is happened. the ist time i sent the engine back to the builder, i filled the manifolds with acetone and found no leaks, i had the intake pressure tested and no problems found.

the 2nd issue it the timing. i can not get the timing to within specs and sound right.
How are you checking the ignition advance?
i misspoke about the distributor, it is a standard prestolite with pertronix ignitor. other than that, the distributor has all the preexisting components below the plate.
I was asking about your procedure for setting the ignition advance.
BASE advance will be in the range of 8* to 10* BTDC at idle speed.
More importantly will be the progressive advance and the total advance. If you are not certain, let us know.


this rebuilt engine has a pertronix ignition in a pretrolte dist. no weights, just a shaft set up. basic.
Any ignition system without advancing flyweights would be an EST system.

the engine sounds the best at 22deg btdc, when i bring it to 8 deg, it runs rougher, not as smooth as 22.
This is at idle?
yes
See above.


the vacuum gauge is very bouncy, violently bouncing from 16-22i in hg.
Vacuum readings will not mean much until you get the ignition advance and the fuel delivery system set up correctly.
the carb was reuilt recently, it ran fine on the last engine and ive made a/f adjustments
The only external adjustments that we can make will relate to the low speed metering circuits.

i have confirmed tdc with a piston stop and it lines up with the timing marks perfectly.
The PPS procedure requires the use of a degree wheel and a temporary pointer.
Was this done?

i used a tdc locator, https://www.amazon.com/gp/product/B000CPCA5G/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
i confirmed that piston tdc was in line with the harmonic balancer and pointer tdc marks
That tool is a PPS..... positive piston stop. The operative word is "Positive".
It is to be used along with a degree wheel and a wire pointer.
With the degree wheel and pointer in place, and the PPS inserted into #1 cylinder spark plug port, you will gently bring the crankshaft around until the piston is stopped by the PPS. Key word "gently"!
NOTE: we want to stop the piston at around 30* before the top of it's stroke. Not 10* and not 15*....... 30* is more accurate!
You will adjust the pointer to approx 30* from the ZERO on the wheel.
You will then rotate the crankshaft in the opposite direction until the piston is again stopped by the PPS.
You will then re-adjust the pointer.
Next you will AGAIN rotate in the opposite direction until once again the PPS stops the piston.
Continue doing this (and adjusting the pointer) until you can come up with an equal degree split on either side of ZERO.

If you cannot reach 30* +/-, then the PPS is either set too deeply or not deeply enough.
Make the adjustment to the PPS, and then continue.

Once the "split" is equal (again... shoot for a 30* +/- split), you will remove the PPS and bring the crankshaft around to where the pointer aims at ZERO on the degree wheel.
DO NOT bump the pointer!
If the pointer is bumped, you will need to start over.

Now and only now can you check the OEM TDC markings against each other.
If they align, all is good.
If they do not align, then this will need to be corrected.

Reasons for not aligning:
.... the outer harmonic balancer ring has slipped against the inner hub. (there is a rubber isolator between the two)
.... the corresponding TDC tab has been bent.


.


what am i missing. i have never had an issue like this before and i am stumped
the engine has already been back to the builders and they claim there is no issue what so ever with it. so how do i ecplain the vascuum gauge dance and the timing issue?
Somewhere, something is being over-looked.
thats why i have brought my troubles here, i know with all this knowledge, someone will have the answer, or in reviewing these posts, something will click in my mind and i will resolve this issue once and for all.
Yes..... that's what we are all hoping for! However, our help is only as good as your skill level! (no offense!)


if the water in the oil is caused by the manifold back pressure, whats the fix for that?

i know the truck cams have an overlap in the valves which could cause seawater to be sucked in so what to do?
Is the camshaft phased in correctly?
I dunno
THE engine was built by a rebuilder in maine who "BUILDS 30 5.7 sbc engines a week, i know what i am doing" well, maybe ....

While it would be rare, there is a chance that the two chain sprockets may not have been indexed correctly.
There are several methods for checking this.
The most simple method (yet somewhat involved) would be to remove the front cover and take a look.
If the camshaft profile specs are known, we can use a crankshaft degree wheel and a dial indicator (on a cam follower) to see where the valve lift begins and where it ends (related to crankshaft position)
This is quite involved, and is typically not for average Joe.

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kghost said:

I guess you missed my post

Boats engines especially out of the water HAVE NO BACK PRESSURE...........they are basically open exhaust.

Run them on pallets all the time! Run it at will and don't worry about squat!

Three common ways water gets into oil,

1. blown head or intake gasket,

2. leaking/cracked manifolds, elbows or their gaskets,

3. cracked block/head.

Smoke test is the best test, pressure tests is second for finding leaks.........not sure what the acetone does but evaporate.......


Reread and answer whether rotor lines up with number one plug wire on cap when you are at TDC. If not you have a distributor or cam timing issue

I am also assuming you know which cylinder is number one.........


Water exiting the elbows is the first place water combines with the exhaust so it would have to be able to travel backward into the manifolds.

In the water under certain circumstances that can happen especially if the engine spins backwards after shutting down....seen it happen many times.

But on a pallet with open exhaust and the water shooting far away from the elbows so to speak this should not be a concern.

One other mention....this whole bit of degreeing the cam and finding TDC as described in the reply..............WTF..........The engine builder should have done all this.
You as the end user should not need to do any of this, That is what you paid for!!!!!!!

All the possibilities of harmonic balancer issues and timing marks being off is retarded........that would only apply if you assembled the engine yourself!

And all the engines I have assembled I have never used any of those tools. Stock set ups. New timing chains and sprockets, marks all lined up, priceless!

never had an issue!

When using aftermarket cams and looking for performance related gains and wanting precise numbers then use those. Stock, not so much. When everything is assembled correctly 99.9% of the time all is good!

.1% of the time you will find a cam that is out of wack so retiming the timing mark to ballancer is required.



And do everyone a favor.

DONT FOLLOW RICARDO's METHOD of answering posts.

It makes it very difficult to understand who is saying/answering what

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forum bully said:

I guess you missed my post

Boats engines especially out of the water HAVE NO BACK PRESSURE...........they are basically open exhaust.

Run them on pallets all the time! Run it at will, and don't worry about squat!
I will caution the OP as per my previous post.
If flat tappet cam followers, run it for the 15 to 20 minute break-in duration.
After that, run it after it has been installed so that the engine can be loaded.


Reread and answer whether rotor lines up with number one plug wire on cap when you are at TDC. If not you have a distributor or cam timing issue
Incorrect and/or incomplete info.
First, this would be #1 piston @ TDC C/S only.
TDC comes around twice per one complete engine cycle.
For checking the distributor indexing, you will want to be on #1 TDC C/S.



One other mention....this whole bit of degreeing the cam and finding TDC as described in the reply..............WTF..........The engine builder should have done all this.
You as the end user should not need to do any of this, That is what you paid for!!!!!!!
And just what if..... (IF being the operative word)...... they did make a mistake?
Is this to suggest that he NOT check it?
Perhaps you would benefit from reading where the OP mentions the 22* advance in order for this engine to run more smoothly.

All the possibilities of harmonic balancer issues and timing marks being off is retarded........ that would only apply if you assembled the engine yourself!
wow.... what a degrading comment to make to the OP!

Again..... what IF this was over-looked and was not verified.

Jack, if you have a crystal ball, please share what you have learned from it.

And all the engines I have assembled I have never used any of those tools. Stock set ups. New timing chains and sprockets, marks all lined up, priceless!
never had an issue!
Jack, need I remind you of a few years ago when you mentioned "on forum" that you do not build engines?


When using aftermarket cams and looking for performance related gains and wanting precise numbers then use those. Stock, not so much. When everything is assembled correctly 99.9% of the time all is good!
No disagreement with that!

.1% of the time you will find a cam that is out of wack so retiming the timing mark to ballancer is required.



And do everyone a favor.

DONT FOLLOW RICARDO's METHOD of answering posts.

It makes it very difficult to understand who is saying/answering what

Yes.... for those of us who are color-blind..... I would certainly agree.
Otherwise, it would appear that Jack is the only one having difficulty.

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stang32 said:

ok, well here is some info for you,
backpressure was not the right term i should have used, what i was implying was that i know that marine cams(stock) have the lobes very close and can cause slight suction back in frm the exhaust which in turn can bring water.

completely rebuilt engine, from rebuilder, had water intrusion, engine sent back, torn down and gone over frm top to bottom, reassembled with ( i hope) all new gaskets, new exhaust kits and intake pressure tested. engine reassembled and water leak a second time, why? where?
how do you pressure test exhaust manifolds & risers?


rotor/plug wire relationship? really? if im setting the timing, you can pretty much assume the rotor is in the general vicinity of the #1 plug wire since the engine is running. once you move the distributor to adjust the timing, then you have dialed it in , no?
Well...... that is basically correct.
The orientation of the distributor rotor is of little importance as long as the cap is wired correctly for the firing order.

This does not necessarily apply to systems that use an indexed and # labeled cap.


yes i basicly dismissed all those ideas about degreeing the cam and such,
To my knowledge, no one mentioned degreeing the camshaft. The mention of degree checking the cam was to explain one method of seeing if the chain and sprockets were indexed correctly.

The PPS procedure is quite different.
It is used to check the accuracy or inaccuracy of the OEM TDC markings.


this is a standard rebuild, nothing special, or Hipo. the balancer has been checked and i matched it up to another and it is in the same spot.
before i put hte timing cover on, i confirmed the 2 sprockets were lined up correctly and the piston was at TDC.
Well, that would have been nice to have known prior. (but no harm/no foul)

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RicardoMarine said:

Jack, your responses will be in black font..... I will respond in blue font. Clear enough?

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stang32 said:

Rick said:

Jack, your responses will be in black font..... I will respond in blue font. Clear enough?

Click to expand...

LOL
I'm glad that you liked that!

oh, btw, it is a roller cam engine, 1 piece rms, vortec style heads with a standard marine rebuild,
before i put the timing cover on, i verified the 2 sprockets lined up perfectly and the #1 cylinder was at tdc
Excellent! We can remove that from the list!

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kghost said:

One thing to question, you have riser spacers??? WHY?
Why would one question him?
If Stang is using risers/spacers between the manifolds and elbows, I am sure that he has a good reason for it.

Are you using the correct gaskets? This is a potential water leak location. If the gaskets are not orientated correctly they could cause a leak into the exhaust manifolds.

Second, you question cam lobe overlap.

The cam used is a pretty much standard truck cam, 260 hp
The lift Separation angle and overlap are very mild and there would be very little if any chance for "reversion" to occur.
That would be lobe separation.

As far as distributor rotor line up. The rotor should be pointing to approx 5 o'clock looking at it from the front of the engine
Yes.... I agree that this is a better scenario.
However, it is not absolutely necessary as long as the plug wire orientation (in the cap) align with the firing order as per rotor indexing.


Next question, why are running a NON Mercruiser distributor/ignition system?
The factory Mercruiser electronic ignition system is bullet proof!!!
That would be his choice.... correct?
I'm not a fan of EST, nor am I a fan of the old Prestolite with the Pertronix kit.
Stang..... can you elaborate on the ignition system for us?

Due to this I would be very suspect of the distributor as a possible cause to your timing issues. Is it possible the distributor is in a retarded state by the way it is set up inside? without seeing the internals it is hard to tell.
He can rotate the distributor housing (as needed) to correct any indexing issue.
But again...... I agree that indexing it as to aim the rotor tip towards #1 cylinder @ TDC C/S is best!

If you can get a different dist maybe swap and see if you can get the timing where it needs to be,
Stang's issue is apparently during idle speed.
In other words, he is having a BASE advance issue, not an issue with the Progressive and/or TA.
At idle speed, no mechanical advance will be occurring..... unless of course, the flyweight return springs (governor springs) are rust compromised or broken!

Question, you are sure you are timing off of number one cylinder? Just to be sure which cylinder are you using? (location) and move the pick up as close to the spark plug as possible. it is not suppose to be at the distributor.

I have a stevens digital timing light, when first turned on i have to set it to ZERO by pushing the advance/retard buttons. Does yours work the same? In other words when I first start the engine it will read ~ 19 degrees advanced and I have to set it back to Zero....Not sure the craftsman works that way.

I would suggest that you use your timing light in "Standard Mode", and forget about the digitally advancing mode for now.
Better yet, use a standard old school timing light!

Maybe try a standard non advance timing light and see if results are the same.
Yes!

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Docksidemarineservices said:

Nothing wrong with running that engine like you have it. Do it all the time.
No disagreement there.
It would be running it for a long duration that would be an issue, as I'm sure you know.

I know a man who bought a fresh SBC Marine engine.
He installed it, ran in while on the trailer and on the garden hose muffs for 6 hours, thinking that he was breaking it in.
He glazed the rings/cylinder walls of which prevented a true break-in.
This forced him to go back to square one.


I would be looking at the distributor for this issue. I watched the videos and sounds like wires are crossed, I know you checked them a dozen times....Try a different ignition system.
Pertronix Ignition systems are junk right out of the box.
Fully agree!

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kghost said:

One thing to question, you have riser spacers??? WHY?
thats wha t this boat needs. its a 29' searay, not that that matters.

Are you using the correct gaskets? This is a potential water leak location. If the gaskets are not orientated correctly they could cause a leak into the exhaust manifolds.
im using the gaskets sierra sent, the good metal ones with graphite coating

Second, you question cam lobe overlap.

The cam used is a pretty much standard truck cam, 260 hp
The lift Separation angle and overlap are very mild and there would be very little if any chance for "reversion" to occur.

intake 394 lift
Exhaust 404 lift

Not much to worry about there.

As far as distributor rotor line up. The rotor should be pointing to approx 5 o'clock looking at it from the front of the engine
not that it matters, it actually is at 5, well maybe 4:50



Next question, why are running a NON Mercruiser distributor/ignition system?

the boat was purchased with the prestolit in it, i dont know why, it just was.

The factory Mercruiser electronic ignition system is bullet proof!!!
agreed


Due to this I would be very suspect of the distributor as a possible cause to your timing issues. Is it possible the distributor is in a retarded state by the way it is set up inside? without seeing the internals it is hard to tell.
yesterday i put another prestolie dist in, since i had it laying around. this one had points with the same results

If you can get a different dist maybe swap and see if you can get the timing where it needs to be,
done

Question, you are sure you are timing off of number one cylinder? Just to be sure which cylinder are you using? (location) and move the pick up as close to the spark plug as possible. it is not suppose to be at the distributor.
the pertronix was new this past spring.
i already moved the pickup all around the engine, to each plug, the mark moves accordingly and the cylinders are all firing.,i normally put the timing light pickup right next to the plug but in the video it may have been by the dizzy because i was moving it all over the place to check for variations, none found.


I have a stevens digital timing light, when first turned on i have to set it to ZERO by pushing the advance/retard buttons. Does yours work the same? In other words when I first start the engine it will read ~ 19 degrees advanced and I have to set it back to Zero....Not sure the craftsman works that way.
when the light is disconnected from power source, it resets to zero,

Maybe try a standard non advance timing light and see if results are the same.

At this point I am not sure what else to suggest.........where are you located? You mentioned Maine. I am in Mass.

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Docksidemarineservices said:

Nothing wrong with running that engine like you have it. Do it all the time.

I would be looking at the distributor for this issue. I watched the videos and sounds like wires are crossed, I know you checked them a dozen times....Try a different ignition system. Pertronix Ignition systems are junk right out of the box. Try the Delco est or any other distributor just for testing.

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RicardoMarine said:

Stang, I have watched both videos where you show the engine running with a BASE advance of 8* and of 23*.

I could take most any SBC and increase the advance from 8 to 23 and it would still run. In fact, RPM would increase as the advance increased.
Your engine should run with either 8* or 23* advance at/near idle speed.... although you will want to be at the OEM number.
its funny you say that becaue the builder is emphatic about " there aint no sbc that will run on 23*, blah blah blah blah blah

However, the 23* BASE advance will cause it to "buck" during cranking. That is simply excessive to fire up on.
yes agreed, kinda. it bucks actually @ around 35, ask me how i know


Questions:
1..... Does it fire up on 23* BASE advance, or does it "buck"? fires up
2..... Does it fire up more easily with 8* of BASE advance? no
3..... Are you able to view the progressive advance as you leave idle RPM and move up to let's say 2,000 RPM? i have not checked but will, but how is that prudent to my base timing issue. and bouncingvacuum gauge
4..... if so, starting with a BASE advance of 8*, what numbers are you seeing at 2k RPM? tbd

As for Jack's question regarding which cylinder you are using for ignition timing....... of course it must be cylinder #1 spark plug cable.
If you were NOT using cylinder #1, you would be seeing an error of 90* plus the BASE advance.
Point being...... it is very doubtful that you have made an error here.

finally some validation ,

.

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Originally Posted by RicardoMarine

However, the 23* BASE advance will cause it to "buck" during cranking. That is simply excessive to fire up on.
yes agreed, kinda. it bucks actually @ around 35, ask me how i know
Yes...... I'm curious..... how do you know this?


Questions:
1..... Does it fire up on 23* BASE advance, or does it "buck"? fires up
2..... Does it fire up more easily with 8* of BASE advance? no
3..... Are you able to view the progressive advance as you leave idle RPM and move up to let's say 2,000 RPM? i have not checked but will, but how is that prudent to my base timing issue?
OK..... if you do not see the ignition advancing as RPM increases, it may indicate that the governing system (i.e., flyweights and flyweight return springs) are malfunctioning.
By default at idle speed, the springs pull the flyweights back into what we would consider to be BASE advance mode.
However, it would be very unlikely that two Prestolite ignition systems would both be faulty, and in the same way.

and bouncingvacuum gauge
The vacuum gauge reading (bouncing) is picking up on each cylinder as each cycles through an intake phase. In other words, it is sensing the pulsations created by each intake cycle.
Normally, the reading would be more steady.

As for Jack's question regarding which cylinder you are using for ignition timing....... of course it must be cylinder #1 spark plug cable.
If you were NOT using cylinder #1, you would be seeing an error of 90* plus the BASE advance.
Point being...... it is very doubtful that you have made an error here.

finally some validation ,
Yes!

stang32 said:

so, also i dont think i mentinoned it but

the engine is not the engine that came out of the boat, it is a rebuilt engine the builder put together for us, as commonly done, he sends you a motor, you send him a core. if the core is usable, he refunds you a core charge.
Good info, although not much to be learned from it.

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stang32 said:

the engine is roller lifter vortec engine
What that means to you, is that there is no requirement for cam follower break-in.
Install the engine....... start it up...... set BASE advance..... check the progressive advance.... watch for any over-heating signs......, and get onto your break-in procedure in the water where you can load the engine as per the break-in procedure.

But of course, you first need to resolve this current issue!

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RicardoMarine said:

Originally Posted by RicardoMarine
Stang, I have watched both videos where you show the engine running with a BASE advance of 8* and of 23*.

I could take most any SBC and increase the advance from 8 to 23 and it would still run. In fact, RPM would increase as the advance increased.
Your engine should run with either 8* or 23* advance at/near idle speed.... although you will want to be at the OEM number.
its funny you say that because the builder is emphatic about " there aint no sbc that will run on 23*, blah blah blah blah blah
If the builder is talking about a BASE advance of 23*, that is not so. But let me qualify that!
It will run, but it will not run well.
you saw the video, how do you think it ran @ 8* and 23*
do you think 8* was satisfactory?


Plus............. if we were to add the progressive advance (let's say 22*) to a BASE of 23* (= 45* total), it would most definitely undergo ignition induced detonation. You would then be looking at another costly re-build!


However, the 23* BASE advance will cause it to "buck" during cranking. That is simply excessive to fire up on.
yes agreed, kinda. it bucks actually @ around 35, ask me how i know
Yes...... I'm curious..... how do you know this?
just that when i installed the spare dizzy, the timing was way far retarded, like 35-40*, the engine bucked, once moved lower, it fired up nice. 3




Questions:
1..... Does it fire up on 23* BASE advance, or does it "buck"? fires up
2..... Does it fire up more easily with 8* of BASE advance? no
3..... Are you able to view the progressive advance as you leave idle RPM and move up to let's say 2,000 RPM? i have not checked but will, but how is that prudent to my base timing issue?
OK..... if you do not see the ignition advancing as RPM increases, it may indicate that the governing system (i.e., flyweights and flyweight return springs) are malfunctioning.
By default at idle speed, the springs pull the flyweights back into what we would consider to be BASE advance mode.
However, it would be very unlikely that two Prestolite ignition systems would both be faulty, and in the same way.
but my point is, i am having issue with base timing, i will addres advance timing once i resolve this

and bouncingvacuum gauge
The vacuum gauge reading (bouncing) is picking up on each cylinder as each cycles through an intake phase. In other words, it is sensing the pulsations created by each intake cycle.
Normally, the reading would be more steady.
But let's table that for now!
now that that is brought up, i have the vacuum gaige readings from the plugged port on the intake. could that reading be coming frmo those 2 corresponding cylinders or will it even out


4..... if so, starting with a BASE advance of 8*, what numbers are you seeing at 2k RPM? tbd
I am not following you on that one! Ideally, we would see BASE advance, and we would then see an increase in advance as RPM increases.
This is what we call the "progressive" advance. Whether this is accomplished via EST or mechanical, the ignition lead must increase with the engine speed.
I will post an example of an ignition curve graph for you at the bottom of the page.
i was saying to be determined when i check advance (tbd)

As for Jack's question regarding which cylinder you are using for ignition timing....... of course it must be cylinder #1 spark plug cable.
If you were NOT using cylinder #1, you would be seeing an error of 90* plus the BASE advance.
Point being...... it is very doubtful that you have made an error here.

finally some validation ,
Yes!





OK..... this is an example curve graph only.

NOTE:
The BASE advance is not shown in the vertical scale to the left side.
What is shown in the horizontal scale, will be the progressive advance that is produced by the flyweight system.... or by the EST system if so equipped

When doing the math, BASE must be added to the progressive number.
However, when strobing your timing marks dynamically, BASE will be seen as included within the reading.

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stang32 said:

i will be going to my local boat salvage yard later and pick up a thunderbolt ignition system and throw that it but as i mentioned earlier, i already installed a 2nd pretolite with the same results.

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stang32 said:

yes i agree, poe, so i already changed the distributor, time to retire that subject. next is the vac.

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RicardoMarine said:

Perhaps so, but have you looked to see if it's offering the correct progressive advance?
If not, the return springs may be compromised causing the BASE advance to be erratic.

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