1994 Mercruiser 350 starter binds sometimes grinds upon engagement

"Hello. I am new to these mess

"Hello. I am new to these message boards and I have a problem

I have already searched through some messages here trying to find more info on shimming starters for the GM Merc 8 cylinder engines, but i cant really find much on the subject..

.Thus, I wanted to post my problem here.

First, the boat is in storage as of today because its just going to get colder and colder from here on out.. Its a rather moot point to post here granted I can no longer have easy access to the engine compartment, however, I am absolutely perplexed at the behavior of the starter and can use some tips here later on if perhaps there is a rogue warm day to peel the cover back and mess with it some more.


Ultimately, this boat.. a monterey 225 cuddy? I think, is my dads and it has sat fermenting under a bad boat cover for about 5 years.

Two months ago I decided to see if there was still some boat left that hadnt rusted or rotted away and removed the cover.. aside from some rotten seat wood and extensive mold/mildew damage the interior seemed ok., but the starter was dead.

I took the starter to a Auto Electric shop to find it to be completely corroded, unusable as a core, and a new one would cost $300+

A week later I took it to another auto electric shop and got a reman gear reduction starter for $75, as he took my corroded one as a core.

I installed this starter, shimless as the original one was, and cranked slow at first (possibly due to engine rust) then faster, then faster, then the engine fired up.--->> absolutely NO starter trouble or wered sounds.

I used the starter a few more occasions to run the engine and verify things were working ok on it.. then i let it sit for a few days or so...

....and invited my brother over to see how well the boat works after its 5 years of neglect. Well, when i tried to fire it up, it seemed to bind up with a force that rocked the entire engine. About every 3rd or 4th try, it would crank half a rev then bind. Sometimes it would grind. It sounded bad and I thought that teeth would be missing on the flywheel.

No teeth were missing upon removal of the starter, however, the reman starter teeth were kind of worn and i believe that may have been how I recieved it.

So then, I ordered a new mercury marine gear reduction starter(i think PG 260) for this model engine, installed it with no shim just like the original, only to have it just bind and kind of buzz upon starting.

A few days later, I got a GM starter shim kit and installed a large shim between the starter and the engine, tried it, and the same thing happens now as with the reman with the exception that it wont crank at all now. It sometimes binds, sometimes grinds and has that "skipping teeth" sound.

I did not shim it any further away as I figured, if its "skipping teeth", taking it further away would aggrivate that condition. After recieving the same bruise on my arm from installing and removing this starter so many times, i simply put the bolts back in the holes and covered the boat for the winter.


So that is where Im at. The flywheel looks and feels really good. Hehe. Oh, the engine, be it a 94 model year, was replaced maybe 7 or 8 years ago and believe it or not has probably less than 20 hours on it. The flywheel should be in top condition, without much use, as when the engine was fresh it started quickly without much starter operation. I have probably used the starter more within the past few weeks as the engine has seen in the first two years of its life(which isnt much at all; probably less than 3-4 minutes of cumulative starter use total).

I also have some questions as to why the starter might seem to bind/grind upon engaging, even though the starter case hasnt changed position...
Does the motor of the starter only engage once the solenoid has pressed the drive gear fully out or close to it? .. Or, rather, if the starter drive gear hits the flywheel head on, preventing its full extension, will the solenoid not be extended enough to engage the starter?

If so, then perhaps these starters are so close to the flywheel that the drive gears are smashing into the side of the flywheel head on and if they engage, grind at the tip without cranking the engine.

Im sorry for such a long post, but this binding (or non engagement) then grinding is rather perplexing to me. In all the starters ive changed i have NEVER had to shim one, so i wonder why this one is being such a problem.

Thanks for reading

__Ben"

..."The flywheel looks and

..."The flywheel looks and feels really good"

It won't be long if you don't shim that starter correctly--and that's been your problem all along. By guessing at what shims it needs you're playing Russian Roulette (with your flywheel and your wallet). The clearance needs to be measured and set correctly.

Jeff

"Just me but I'd get rid o

"Just me but I'd get rid of that gear reduction starter. We had a lot of problems with those things.
For some reason I'm thinking that they had plastic starter drives that always broke. I could be thinking of another starter as far as the plastic drive but I know those gear reduction models were not very good. At least when they first came out anyway.

Jeff is right on the shims needing to be correct but I think you may have another problem besides the starter.
Reason for this is the starter worked right for awhile then took a crap.
The way you say the engine will not turn over all the way makes me think there could be some water entering into one or more of cylinders.
If this is the case the engine would have a hard time turning over if there was enough water to cause a slight case of hydro lock.
I could be wrong about this but a quick check of the way the engine turns with the spark plugs removed will tell.
Also make sure all the cables and the battery are in good condition as low voltage can cause this also.
I hope that you sprayed storage fog into the engine before you put it up. If not remove the plugs and spray some fog in each cylinder and the intake then turn the engine by hand if the starter will not work.
Best that you find why this engine will not turn over before you put it away. If it's the starter that's bad no big deal but if there is water in the cylinders it going to be a real bad deal come spring.

Good luck"

"Thanks for the replies.

I

"Thanks for the replies.

I doubt theres water in the cylinders, but I chave not checked. If the engine is hydro locked, the starter should clunk to engage then sit there.

Sometimes, with the new factory starter, there dosent seem to be an engaging clunk, yet seems to buzz perhaps from the solenoid as if the solenoid is not allowed to move enough to let the motor have power.

Besides, whether its hydro locked or not, the starter shouldnt grind like it does.. its, at least, a starter a problem.


And actually, Id love to try and set the starter shim correctly and properly. But, I am at a total loss to do this the proper way. Ive searched here for some info on starter shimming but there arent really any posts that give any insight on how to do it properly.

There simply isnt the clearance to do much of anything at all down there but fumble with installation and removal..
..Does anyone know any decent ways to actually check the contact between the starter drive and the flywheel? I actually bought a real mercury service manual for this engine and lo and behold is one of the worst manuals I have ever recieved. At $70, upon openning the manual to the starter page, a few pages immediately were separated from the spine, and further, gives NO, NO info on how to properly shim the starter to the engine. The ONLY info it gives is to put the shim back in if there was on upon removal of the old stater. What a horrible manual.

Is there a way to remove a cover or something to actually see what the two gears are doing? The first step under flywheel inspection in the manual says 1> Remove engine.


Thanks !!


__Ben"

Well Ben the only way I ever h

Well Ben the only way I ever had much luck if the new starter didn't work with the old shims and the engine was in the boat was to spray paint the flywheel the best I could install the starter. Then bump the starter a little then remove it and check how far the teeth on the drive went into the flywheel.
This is a real pain to say the least.

The reason I thought you may have water is you say it will turn over. A small amount of water can stop the rotation but would bleed off after a few minutes. I doubt you have a major leak. It's just a thought.

Have you tried turning this engine by hand with a socket and breaker bar on the crank pulley bolt?
I just can't understand this amount of trouble with a 5.7 starter. They're just not that hard to install and have a lot of give. I'd say check the timing but that would not cause the grinding.

Are you sure that you have the correct starter. There are two models for the 5.7. Some engines have larger flywheels.
As far as I know you can not install a starter for the smaller flywheel into an engine that has the larger flywheel on it but the larger flywheel starter will fit into the engine if it should have the smaller flywheel.
Unless you look close at the staters you would not notice the difference in the two.
I believe they also may use different starter drives but I'm not real sure about that.
Most of the marine 5.7 models had the smaller flywheel but some did have the larger one.

"Hmm good idea.

I also have

"Hmm good idea.

I also have just found out that there are two starters for GM 350 engines, apparently a standard and a metric?

The deal is that the reman starter was working just fine for maybe... 2 minutes of cumulative cranking and then began its binding/grinding bit.


This IS very frustrating indeed!! hehe. I was thinking maybe there was a wayto remove some inspection cover for this GM 350 Mercruiser engine and check visually to see the proper mesh.

I, too, believed a starter swap to be really simple. I am wishing now that I had measured completely the old corroded one that originally came with it.

The factory fresh one i ordered from Mercury Parts Express online from a place called Marinemax here near atlanta. (I guess marinemax gets the orders and fills them) but they are direct replacements.

The engine model that im dealing with is 0F416579 and if you put that into mercury marine's parts express site, you get the same part number for starter assemblies no matter if you choose between the PG 260, PG200, or the direct drive.

Further, Marine max called me, and the guy said that the part number that he got to fill from M.M. Parts Express was outdated and "superceded" with a new one. I was told it was identical in function/spec and was just "updated" ie, he said if he requested the part number M.M gave him, he would get this new, updated one anyway.


So I dunno. Its very difficult though, as I just got to the boat sometime in August while it was still warm and it was none other than this starter situation that has prevented me from taking this boat out. (The first auto electric shop I took the starter to kept it for like 3 weeks to tell me that it was corroded)

But anyways, ultimately, the behavior of the starter sticking/binding/not engaging, then grinding seems very unusual to me.

I will continue to frequent here occasionally in the future and welcome all advice, and post the rest of this scenario if it ever gets fully solved....

Thank you for the replies


__Ben"

"Oh, Im sorry..

..No i have

"Oh, Im sorry..

..No i havent tried to crank the engine by force of the crank bolt. Actually, I doubt theres clearance for that anyways.

But, the engine ran just fine when it was shut off last, and further, hydrolocked, damaged rod, whatever may be, the starter should not grind. It should clunk to engage then stick. Sometimes it buzzzes as if (perhaps) the solenoid is not allowed to extend to its full travel, thus not engaging the motor and sometimes it grinds and sounds expensive


__Ben"

You're correct on the hydr

You're correct on the hydro lock and the rod. This was just a thought Ben. Let it go it's not the problem. There is something very minor that is being over looked.

I'm sorry but without seeing it I can't tell what it is at this point.

As I said a 5.7 starter is not hard to install and they have a lot of room for error.

You say you installed a large shim at first. Why?
You only need to move very small amounts until you find the correct placement.
To just throw a thick shim in makes no sense.

If there was no shims at the start of the job one small or thin shim should be all you need.

It may work if you remove the shim you have and try using a much thinner shim to start with.

If you have a good shim kit you do not have to remove the starter to change the shims. One side of the shim should have a slot so one bolt can remain in the starter to keep it inplace.

"I tried a large shim because

"I tried a large shim because it seemed as if the starter was buzzing before, as in the solenoid was buzzing, perhaps unable to even extend the drive gear out enough to trigger the actual motor. It would seem that if the starter was that close to the flywheel then a larger one would probably be needed to free it up adequately.


Ultimately, I have no idea why it was behaving as it was earlier. I would assume however that if the starter is actually engaging, yet binding with the one large shim that it may still be too close to the flywheel.

The grinding i cant explain. Sometimes it would do it, sometimes not. But with the shim its either actually applying torque to the flywheel but is bound somehow or it grinds. I have inspected the teeth on the starter motor only to find no wear indicating where its grinding, none at either the front-facing end of the gear nor at the teeth tip; Perhaps because the starter is so new.

Its just a mystery for now i guess.. heh. Its next years problem. I tried to be nice to it this year and give it a breather and take it to a lake but it was too mean to me with the starter so i guess it will just sit there and rot some more. Muhahahaha.






__Ben"

"If you can get to the flywhee

"If you can get to the flywheel, you can adjust the clearance with a 0.20 inch wire gage.

1. Disconnect the battery

2. Remove the solenoid and push the bendix into engagement

3. Insert the wire gage. It should fit the gap loosely. If not, add or remove shims until it does.

Jeff"

"I know you've probably do

"I know you've probably done this, but have you checked all elect. connections for corrosion and made sure you have a fully charged battery. You could also bypass the ign. switch at the solenoid to make sure you're getting full voltage at the solenoid. Always check the simple stuff first. Mike"

"Hey thanks for more replies.

"Hey thanks for more replies.

Actually, it would be ideal if i could check the clearance with the starter in place, however, I am not sure if thats possible. The engine is a Mercruiser GM 350 of model year 1994. The engine serial number is 0F416579. Is it possible to remove a flywheel cover or something without removing the entire engine? Certainly if starter clearance was known to be a possible problem then perhaps the makers would allow for proper visual inspection of the starter/flywheel clearance.

If it is impossible to do this with the engine installed then I cannot properly set the clearance on the starter.


As for the wiring I am not sure. The connections are great between the actual motor and the battery, and the grounds seem good. There is, however, what I believe to be a separate solenoid on the top of the engine that allows +12 to go to the solenoid to the starter. This would be the "slave solenoid"? This solenoid is kind of rusty and although I doubt it, it could be lowering the voltage to the starter solenoid.

Perhaps an input of less than 12v to the starter solenoid coulc cause improper engagement.

Ill keep that in mind to test for 12v+ to the solenoid even when it is engaged (Motor wire disconnected, of course)


Thanks,

Ben"

"Ben:

I was afraid you coul

"Ben:

I was afraid you couldn't do it that way. (Thanks GM for such a design!) The other way to do it it this:

1. Pull the spark plugs and ground the coil lead to the block.

2. Wheel it over and listen to how it sounds

3. Try more then less shim until it "sounds right".

The last method is actually more common that the right way, for obvious reasons.

Good luck!

Jeff"

"In the last 20 years I have i

"In the last 20 years I have installed over 200 GM 350 and 305 marine starters.
I never removed a shim from an old starter, or used one when installing
a new starter. - Common install problems -

#1- engine fly wheel ring gear, damaged from old
starter. Turn engine by hand, watch ring gear very closely. Just a
couple of bad teeth can bind or skip. Pull spark plugs and roll engine
by 5/8" crank bolt or chain wrench around pulley. You have to do this.

#2 Starter bolts to long,- even the new bolts that came with starter.
You install starter, pull bolts up tight, threads have bottomed out, leaving
1/8" gap. Starter may work 10 times, each time sounding worst, 11th
time starter binds up.- Install 1 or two washers, to shorten starter bolts.
And pray that ring gear is not damaged.

#3 Bolt closest to flywheel does not have the reduced head size.
3/8" bolt with ½" head. If a standard 9/16" head is used it can bind up
on the dust cover and not fully seat or push starter slightly out of line.
Even the new bolts that came with starter, usually come with the 9/16"
head, and often 1/8" too long. Correct bolt, ½" head $6 Merc dealer.
Normal retail is $ 130 for large old style starter - $165 gear reduction.
We use all gear reduction - works great on small blocks.
Mercruiser will want $250+ for same starter- different box. All are
made by Delco."

"Good point, Jerry. The start

"Good point, Jerry. The starter bolts are SPECIAL in that they have an enlarged section near the head that locates the starter accurately.

Jeff

PS: I've done a bunch of GM starters as well, and I see shims maybe 50 % of the time. I suspect a bunch that you worked on may have needed a shim to locate them just right--they obviously worked, but they could have worked better."

"Hm.

Excellent points, it

"Hm.

Excellent points, it HAS to be something simple. Thank you for the replies.


I will keep these ideas in mind for the next time I am able to work on it.



Thanks again,


Ben"

"I have never seen a shim on a

"I have never seen a shim on a small block marine engine,
since the mid 70s. Factory engines have no shims - I
have not shimmed a starter in 22 years, and they all work
well - if the 3 problems I listed are checked.
A small block Chevy - is not a old Stove Bolt 6.
I don’t think NAPA even has GM shims.
The reason the shop manual did not tell you about shims -
is that they were not used.
If the old starter did not have shims - the new one will not
need one.
Pull the plugs - roll engine by hand - stop and -think - look
closely - think again - your problem will be simple - you just
have to see it. Many bad words may be uttered - but you will win.

Now turn off the computer - and go do it.


."

"gm starters are made a bit di

"gm starters are made a bit differently now days then in the past...never had to shim a starter in 34 years myself either...till i received a "modern" rebuilt starter...factory specs say that there should be a 1/8 space between the installed starter and the flywheel ring gear..when starter is fully bolted and torqued into place....add shims to starter pad bolt closest to block to move gap wider and to the outter starter pad bolt to tighten gap..using a shim fully across the pad shimming both bolts out will not correct the problem..any parts store can give you a shim pack with the required 1/8" rod in it....quite possible that the starter nose cone has cracked from inpropper adjustment of the gap...this allows the starter bendix shaft to wobble when starter soliend is trying to engage...sounds crazy i thought at first, but call any gm dealer or good parts store,,,gm car starters are sold with shim kit if it may be required for that appilcation thru the automotive parts stores...as to wheather or not you can get into the area to check the gap is going to depend on engine hull design........."

"..."...never had to shim

"..."...never had to shim a starter in 34 years myself either...till i received a "modern" rebuilt starter"

Now that might be the answer to a bunch of starter problems. It's entirely possible that when the starters are rebuilt, the rebuilder has a cut taken off the beat up mounting surfaces, and that requires a shim to correct. Then again, non-GM starters made in ?? might not be as accurate. Either will require shimming to get right.

My 85 Pontiac Fiero (2.8 V-6) came from the factory with a shim, and I've seen other GM cars (Cadillac 4.9 V-8s) that always seem to need a shim.

Go figure...

JEff"