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88 OMC 504V timing power issues

C

captsully

Member
"Sorry for the long winded mes

"Sorry for the long winded message here...I just dont want to leave anything out.

I bought an 88 Bayliner cuddy last fall and took it directly to the river to have a mechanic check it out. The timing was 2 degrees off, which he set and we then took it for a test run. The boat ran great and easily cruised at 55mph+.

I then had another mechanic/shop perform an outdrive servicing/engine alignment, swap the prop with another which was in the boat, and winterize it.

In the past 2 weeks, I replaced the exhaust manifolds, risers, bellows, distributor cap/rotor/condenser/points, spark plugs/wires, fuel filter, oil filter, and put in 10/30 synthetic oil. After all that, I couldnt start the engine. I rotated the engine manually to show 8 degrees BTDC on the tuning plate. I then removed the distributor cap and saw that my rotor button was pointing towards the 8 wire, not the 1 wire. So...I unpluggued all the wires and rotated them around in a clockwise rotation so now the 1 wire is in the 8 wire slot and the 8 is in the 4 slot and so forth. It started right up. I have no idea why the factory location for the wires didnt work (I dont know what the old wire config was--sorry)?? I then set the points (.018) and timing (10 BTDC)...but I am NO mechanic. There is now a knocking sound coming from the distributor, the engine seems to be missing a bit and the tachometer does not show RPMs beyond 2000?? If I rev it up (attached to the water muffs), the engine responds nicely, but the RPMs only show 1800-2000 RPMs...yet the engine seems to be above that?? I confirmed the plug wires were WELL seated in the cap---so that is NOT the clicking/knocking sound.

I then took it out to the river tonight to try it out and the boat started fine, idled fine, and moved along at no-wake just fine. But when I tried to open it up, it just wouldnt go faster than 10mph?? The tachometer did not read above 2000, but the engine seemed to be reving above 2000--but not full power/RPM. It seemed to me that the prop was slipping. Maybe the hub was bad in the prop I had put on in the fall? But that shouldnt stop the tachometer from showing RPMs above 2k. Could something with the outdrive servicing/engine alignment be causing my loss of thrust/power issues?? What could be causing my tachometer/RPMs issues? I do not have a digital timing light which shows the RPMs...but the tachometer was dead-on last fall (checked by the mechanic).

To recap:
- Clicking/Knocking sound from distributor
- Plug wires rotated one position clockwise
- Tachometer not showing more than 2k
- Engine missing a bit
- No thrust/power in river

Thanks everyone!!
Sully"
 
"I'm not sure what the noi

"I'm not sure what the noise from the dist is unless somehow you got the wrong parts, cap or rotor. It really sounds to me like you are probably only running on 6 or even 4 cyls. I don't like what you had to do with the plug wires to make it start. The only true way to find #1 is to crank the engine until the piston is at TDC for #1 on the compression stroke, then the rotor will be pointing at #1. I'm sure you have but I would really go back over everything you did, especially the plug wires."
 
"One other thought (althou

"One other thought (although it's pretty far out there) Which 5.0 ltr engine do you have GM or Ford, dist at the back or front. I was just wondering if by chance you might plugged it for the wrong one? The firing order for the Ford's are 1-5-4-2-6-3-7-8 and the Gm's are 1-8-4-3-6-5-7-2....could be running on 4 cyl's but it would be really rough (told you it was way out there!)"
 
"and get the 10-30 oil out of

"and get the 10-30 oil out of there. Straight 30 or 20W50, or 25W40. You can use synthetic, but go heavier. There's no engine oil cooler on your OMC."
 
"GM...distrib in rear.

I us

"GM...distrib in rear.

I used the harmonic balancer to determine where TDC was and then looked at the rotor, which was pointing at 8, rather than at 1 (or where I felt one should be).

I went over the plug wires/firing order 20 times. My neighbor did too.

The manual and oil cap called for 10w30. Is this a really bad thing? Would it be better to run 20w50?

What are the symptoms if the ESA unit is flaky?

Thanks all!
Mark

Thanks all!
Mark"
 
"If the ESA stays engaged it w

"If the ESA stays engaged it will act like a very bad miss. You can rule it out quickly by unplugging the 2 wire connector (purple and gray wires, this will kill power to it and disconnect it from the coil. If that is causing it then you need to determine if the unit is faulty or if it's being activatd externally, like a bad shift cable. Don't leave the ESA unplugged permanently as it will make shifting out of gear very hard and possibly cause lower unit problems.

For the oil...which manual???? OMC has always pushed their own 4 cycle Cobra oil which is 30, I know some guys are running Merc 20w-50 but no one I know ever runs 10w-30....if it says it on the oil cap, wonder if the engine was ever replaced (or the oil cap)????"
 
"The 2-wire connector is found

"The 2-wire connector is found exactly where?

I have the original OMC manual that came with the boat. It just says 30 SAE on one page and 10w30 on another. The oil cap definitely says 10w30 on both sides. Weird.

After doing all the R&R work...I worked on the engine for about 16 straight hours trying to figure out the cause of the:
- weird plug wire config on the distrib
- knocking distributor
- flakey tachometer
- missing engine

Maybe I have a short in the distrib causing all the above symptoms?

After taking it to the river (with my kids) last night, and only being in the water for 20 minutes...I was too pissed off to work on it anymore. I dropped it off this morning at the boat mechanic. Hopefully he will find the problem quickly and it wont cost me too much.

With that said...if you have any suggestions on what he should try/not try, I will pass it on. I'm not sure if he will like that too much though...he may be the "proud mechanic" type??

Thanks all!!
Sully"
 
"I can sense your frustration.

"I can sense your frustration....to find the ESA connector just follow the 2 cables coming from the unit, one will have a 4 wire plug which goes to the switches and the other is the 2 wire I mentioned above.

I'm sure the mechanic will have his own PD process, let us know how you make out, thanks."
 
Hey Bob...I'm laughing at

Hey Bob...I'm laughing at myself as I ask this question...

What "unit" are you referring to? Follow the 2 cables from the ???? I have only one thin black cable coming from the distributor.

BTW...where is the tachometer getting its feed?

Thanks!
Sully
 
"Sorry Mark...the ESA unit is

"Sorry Mark...the ESA unit is a "Black box" module usually mounted somewhere near the carb just off to the side near where the shift cables are attached. Maybe this exploded view will help you find it. See item 71, this whole assembly should be mounted just off to the left of the carb as you look at the engine from the front. The thin black cable you mention is feeding the coil from the points. Your tach gets it's pulses from the negative post of the coil. Should have 3 wires on there, black from the dist, 1 gray from the ESA and 1 gray going to the tach.

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"
 
Hmmm? Now you have me thinkin

Hmmm? Now you have me thinking. Yes...this large metal bracket/assembly is mounted to the left/rear of my carb. It holds several cable mounts as well as the fuse holders. I had to remove the 2 bottom bolts and push it to the side to allow my valve cover to be removed. I was pushing this metal bracket contraption around quite a bit to get the valve cover out/in. I wonder if I messed something up there??
 
"somebody put an oil cap off o

"somebody put an oil cap off of a car on there at one time or another.. or maybe you have a car engine swapped in at some time... check to see if the distributor, starter and carb are marine parts"
 
"How can I tell if they are MA

"How can I tell if they are MARINE parts? Actually...can you just take a look here: http://rides.webshots.com/album/561348175yADjFQ?vhost=rides

Shoot...I just saw something on the engine photos. I had already thrown away this old distributor cap and wires...but as you can see by the photo, the number 8 wire position is actually connected to the number 1 wire and goes off to the right. So...that is how it was connected before."
 
"I was thinking something like

"I was thinking something like 20 degrees off. But that really isnt a big deal, right? The engine shouldnt run differently. I assume the person who put this in did not account for the slight twisting motion of the distributor falling into place."
 
"I guess the last thing I woul

"I guess the last thing I would do except you don't have the boat now? would be to use some insulated spark plug wire pliers and pull them off one at a time while it's running and listen for a change in RPM's, should be able to hear which cylinders aren't working (if any) and go from there to see if it's electrical or mechanical."
 
"looks like marine parts in th

"looks like marine parts in the pics, but you can look for a stamping in the starter housing: SAE marine J1171, and dist should have a tag that says same."
 
"The boat mechanic had not yet

"The boat mechanic had not yet started on my boat, and did not know when he would....so I picked it up and will find another mechanic.

In the meantime, I thought I would take another crack at it.

The engine starts right up...but is definitely missing at higher RPMs and the tachometer will not got above 2000. Maybe the tach is getting its feed from one of the cylinders which is missing? I will see if I can find some rubber gloves so I can pull the plug wires one at a time. If the engine sounds worse, then I can assume that cylinder is firing.

Any thoughts?

Thanks all!!"
 
"Make sure those are good rubb

"Make sure those are good rubber gloves with no holes or splits, the spark will take the path of least resistance and you don't want that to be you!

The tach gets it's pulses off the negative post of the coil so it's not affected by any one particular cylinder. You could try this though, it's been known to happen where a bad tach or ESA can affect the spark. Check your negative post on the coil, should have 3 wires 2 gray and 1 black. Take the 2 gray off, one comes from the ESA and the other the tach, leave the black one on as it's from the distributor (points)then try it, this eliminates anything exterior to the coil that could be affecting it."
 
"I would love to try this toni

"I would love to try this tonight...but I have to pull my boat back out of the garage to hook up the hose and it is just so late when I get home. If I dont get to it today, I will definitely do it on Friday when I'm off.

What about the distributor knocking. Could this be the mechanical advance? Could the mechanical advance be sticking and cause the missing at higher RPMs?

Thanks!
Sully"
 
"Probably wouldn't hurt to

"Probably wouldn't hurt to take the points plate off and look at the weights and springs to make sure there is nothing loose in there. The best test for that is a timing light with advance feature on it. If it wasn't functioning correctly it would create more of a timing issue which would show up more like loss of power, engine really sluggish, even pinging maybe at the higher RPM's but it shouldn't be like a miss."
 
"I dont believe you can actual

"I dont believe you can actually see anything here...but I uploaded some new distributor photos on page 2 here: http://rides.webshots.com/album/561348175yADjFQ?vhost=rides

BTW...I dont know what the stainless steel spring band is actually for that surrounds the copper spring band which is rivetted to the points bar. The copper is rivetted, but the stainless steel band is just sitting there. I have no idea what it is for or if it is necessary or if it is a problem?

The kit I bought is here...but it does NOT show the copper spring band (it only shows the stainless steel one--which in this picture is rivetted to the points bar??): http://www.wholesalemarine.com/pc/SIE-18-5275/11000604/OMC+Ignition/Tune+Up+Kit+ (+Prestolite+V-8+Screw+Cap+).html

I'm confused!"
 
"I had a simalar problem, turn

"I had a simalar problem, turned out to be the new rotar arm looked identical but the flat edge what locates it to the shaft was in a different position making the timing fire on the wrong cylinder. worth checking."
 
"Did you take both distributor

"Did you take both distributor pictures from the front. If so, look at them and see where the black wire is on both. A reply above mentioned looked like 45 degrees diff. Looks more like 90. Many that's why when reversing spark cables it started. Most often noise from the dist. is because of wrong rotor or improperly seated one."
 
"[b]BTW...I dont know what the

"BTW...I dont know what the stainless steel spring band is actually for that surrounds the copper spring band which is rivetted to the points bar. The copper is rivetted, but the stainless steel band is just sitting there. I have no idea what it is for or if it is necessary or if it is a problem?

Pretty sure the stainless band is to give the proper spring tension to the points without it attached properly your points can float, did you check them with a dwell meter? If they float your timing can as well."
 
Glenn...good eye. Sorry for m

Glenn...good eye. Sorry for my stupid photography. I can see where this would present some definite confusion. I actually took one from the front and one from the back. If you look hard you can see the round thing behind it flips sides. Sorry about that...and thanks for the keen eye!

Sully
 
"Bob,
The steel band is defin

"Bob,
The steel band is definitely NOT rivetted to the points bar. It came as a separate piece and I have it wrapped around the copper band. Everything is screwed to the single connection point in the rear though...but I'm not sure it is actually doing anything (good).

I've uploaded a couple more pics here highlighting where the steel and copper bands are. The red arrow is pointing at the end of the steel band which just sticks out. The yellow trace is the copper and the red trace is the steel. http://rides.webshots.com/album/561348175yADjFQ?vhost=rides&start=24"
 
"In your pic showing the red a

"In your pic showing the red and yellow, the red is the stainless and it shows going around the outside of the copper and is attached to the screw but the other end is floating so in effect doing nothing (if my eyes are right?) So how about putting the stainless piece inside the copper, the one end is attached to the screw and the other end with the little hook will rest against the copper and actually put more tension on it where it hits the dist cam."
 
Your eyes are correct. I had

Your eyes are correct. I had not thought to put the steel band inside the copper one. Hmmm? I will give this a try tonight or tomorrow (I'm off Fri-Sun). My only concern is whether or not it will fit...considering that the screw down terminal does not move and is the same screwn down terminal for everything. In other words...I'm not sure the steel band will fit under the copper band...but I'm gonna try!

Thanks for thinking outside the box!

Sully
 
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