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2003 5.7L 350 MAG MPI - Set Timing - Adjust Distributor

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abl1111

Regular Contributor
Geez - I own the Mercruiser Shop Manual for my engine. I cannot for the life of me find anything on timing the engine ( namingly adjusting the distributor ).

I do not own any specialty tools. I'm hoping I can do this with just auto timing and tach tools. If not, let me know. I do believe that a wire has to be jumped to fool the engine its in a test mode.

Can anyone provide detailed directions ?
 
Top dead center of compression stroke, index the(HVS) distributor to the #1 cylinder and send it. The ECM controls the timing. No timing light needed. Once you have the (HVS) distributor installed and the engine running you can rotate the (HVS) distributor slightly, one direction or the other, if the engine sounds a little rough at idle.
 
I believe the distributor has a very specific location for proper starting. I'm finding/ have found ( the hard way ) when it's too far one way and too far the other, the engine will not start. I'm trying to find the optimal location.

Also, is possible to tighten the dizzy while the cap is on ?
 
abl1111 said:
I believe the distributor has a very specific location for proper starting. I'm finding/ have found ( the hard way ) when it's too far one way and too far the other, the engine will not start. I'm trying to find the optimal location.

Also, is possible to tighten the dizzy while the cap is on ?
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Yes.....
 
I have learned not to trust everything I see online and have been burned several times assuming 'the pros' are always right, or with 1/2 the info I need ( not helping me realize, as a weekend warrior, the pitfalls that may occur ). This site has been a great resource and directed me in the right direction, almost always.

I have one mark on the crankshaft pulley harmonizer - can I assume that is the TDC mark ? And, there is a cutaway where the TDC mark looks like it would line up with to show TDC. Is this correct ?

Is it a bad idea to turn the crank via the crankshaft pulley nut - over tightening that can have dire consequences. Another way to turn the crank pulley ?

Thx
 
Well there's that but finding TDC is not so complex that you will find very much contradictory information.
You pull out number one plug, stick your finger over the hole and turn the crank until you feel the air pushing out. That means the piston is rising with both valves closed (compressing). Continue turning crank until timing marks line up. That's all there is to it.
Yes you turn the crank with harmonic balancer bolt. This won't hurt it in any way.
If you miss go around again, don't turn the engine backwards to align the marks.
 
​From another site:

“ agree with AD, NEVER turn a motor by the crank bolt, because you will snap off the bolt and need a new crank (which is usually a complete new motor)

just bump it around with the starter or pull the plugs and grab the belts “
 
If the engine is so tight that you can't turn it easily with a wrench on the crank bolt then you have much much bigger problems. If you feel like the bolt will snap off when you try to turn it the engine is probably f@@cked
 
If the engine is so tight that you can't turn it easily with a wrench on the crank bolt ...............................
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Any well seasoned mechanic should NEVER (even vaguely) allude to doing this!

If by chance that center crankshaft bolt was to break off, you may find yourself pulling the engine out.... and you know the rest of the story.

There are fixtures and tools for this:

Crankshaft center bolt no no.jpg




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Everyone on this site is either here to help or needs help. I've saved thousands of $$$ by seeking advice from others who have the expertise and knowledge I do not. I've also made critical mistakes on my own or from another's direction because, in both instances, I lacked experience and insight to some of the pitfalls. It's sort of like giving directions to open up a tube of toothpaste - you 'assume' the person wanting to know how to open it, will not squeeze on the tube as they unscrew the top.

The point is that it is CRITICAL to provide complete information when giving direction and for users to beware. Obviously all potential problems cannot be captured ( see below ). We all need to have enough humility to know that there's more than one way to skin a cat, and our way might not be the best way, or a common practice - but its worked for you...

For me, I was turning the crank bolt and it was not turning the engine. I did not know why at the time, but realized later ( thankfully before I kept trying to tun the bolt ). I was unable to winterize my engine so I drained the raw water in my engine via the Schrader valve/ air pump. Water dumped out of my engine BUT - unknowingly, it did not come out completely from my raw water system hoses, or raw water pump - so, the impeller in the raw water pump housing was frozen... and, the engine would not turn. Being a novice, I did not realize this. ( I'm still stumped at why the Schrader / pump did not blow out the entire system and protect me from this !!!! ).

Bottom line - I thank everyone for their help. I winterized all and will refocus on finding TDC in the spring. Just glad I was able to find the issue - I would not have without help from this site ), and that I did not "F" up and do more damage by either cracking something in my cooling system due to ice, or snap that bolt by being frustrated and heavy-handed.

So... isn't that bike pump/ scraper valve supposed to dump all the raw water in the system ??? Thank G*D I found this quick... before ice did... what ice does...
 
You better remove the hoses from either side of the engine block and make sure it is drained or you will be setting the timing on a new engine block in the spring. The single point drain clogs and does not allow the block to drain.
 
I was able to start the engine after I heated up the engine compartment. I’d be lying if I wasn’t sh*tting pickles once I realized things had frozen a bit.

I was able to properly winterize the engine, as I’ve done years passed. All ran great. That pump/ drain set up is a false security. It was a close call.
 
Docksidemarineservices said:
You better remove the hoses from either side of the engine block and make sure it is drained or you will be setting the timing on a new engine block in the spring. The single point drain clogs and does not allow the block to drain.
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2x

You better remove the hoses from either side of the engine block and make sure it is drained or you will be setting the timing on a new engine block in the spring. The single point drain clogs and does not allow the block to drain.
 
RicardoMarine said:
Chris, you have just quoted yourself! Are you having a senior moment like I do occasionally? :D
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Nope.

When I make a statement about how it is important to pull the water hoses off the engine block on a single point drain system.....This advice needs to acknowledged.

The OP said "I was able to properly winterize the engine, as I’ve done years passed." His Idea of properly is probably questionable.

Just making sure my advice was not missed.
 
Another item that's never mentioned is watching what happens when you open a drain--water MUST come out, lots of it. If not, there's a debris plug stopping it that must be cleared or water will not drain completely.

A case in point: The port side block drain on my 305 V-8 barely oozed water once opened. Got a hunk of wire and poked it open, and a gusher came out, much of it dirty brown (rust). Imagine what would have happened if I wasn't paying attention since the thermometer outside my window is showing 18 degrees!

Jeff
 
Freshwater cooled engine - only elbows are raw water. Process; run engine to operating temp. Then, pull raw water intake hose, put in bucket with 4 gallons of antifreeze, until pink comes out of exhaust. Done.
 
Yeah this went from a TDC discussion to winterization and I didn’t think to mention it. One thing is for sure - I‘LL NEVER RELY ON THAT PUMP TO EMPTY MY RAW WATER ! What a false security...

is there a way to unclog whatever is clogged to assure that system works properly ?
 
abl1111 said:
Freshwater cooled engine - only elbows are raw water.
Process; run engine to operating temp. Then, pull raw water intake hose, put in bucket with 4 gallons of antifreeze, until pink comes out of exhaust. Done.
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On an engine that is fitted with a Closed Cooling System (what you're calling FWC), there is no need to warm the engine up prior.
The open/closed position of the thermostat has no bearing upon this.

Keep in mind that your pink antifreeze will become somewhat diluted by any residual seawater.
It would be best if you were to drain all seawater from the Heat Exchanger and the Elbows before doing this.


is there a way to unclog whatever is clogged to assure that system works properly ?
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Are you asking about a single point drain system?
If your engine is fitted with a Closed Cooling system, I don't believe that you will have any type of single point drain system on it.

For those who do, I would suggest that you completely remove that silly system.



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Engine at operating temp to remove oil... as for dilution, you’re right - I should dump the raw water from the heat exchanger and raw water side.

I do have one point drain system. There’s a schrader valve mounted near the heat exchanger with narrow diameter air lines And a mercruiser hand pump; pump air at schrader valve adding pressure to raw water side and water rushes out near lower port side..

When it works it works. I almost never use it as my boat is either out or winterized by any deep freeze.

This year I could not start engine to winterize. So I used this pressure system. It was a false security, because you really can’t tell if it empty’s everything. It almost cost me a lot of headache ! It did not completely drain and my raw water side partially froze !!!

Live and learn.
 
abl1111 said:
Engine at operating temp to remove oil... as for dilution, you’re right - I should dump the raw water from the heat exchanger and raw water side.

I do have one point drain system. There’s a schrader valve mounted near the heat exchanger with narrow diameter air lines And a mercruiser hand pump; pump air at schrader valve adding pressure to raw water side and water rushes out near lower port side..

When it works it works. I almost never use it as my boat is either out or winterized by any deep freeze.

This year I could not start engine to winterize. So I used this pressure system. It was a false security, because you really can’t tell if it empty’s everything. It almost cost me a lot of headache ! It did not completely drain and my raw water side partially froze !!!

Live and learn.
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FYI, Do not use the single point drain system, the air valve on the back of the raw water pump can and will get stuck open. In the future, run your engine up to temp, change the oil, manually drain the heat exchanger and pump 5 gallons of AF through the system. Done.


FYI, do not remove the system as suggested.
 
So this is probably a kinda dumb question but why not just undo the hoses and let the water out of the seawater side? With all the coolers and heat exchangers drained there's no chance for water to freeze and damage anything. Besides when you recommission you will be assured that the hose clamps (doubled AWAB brand) are all tight. I'd also take the seawater pump apart and leave it open so that you know to reassemble with a new impeller come springtime.
 
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