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OMC 305 Starter Problems.

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1987Bayliner

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I recently purchased a 1987 Bayliner Trophy that had the engine replaced a few years ago - The first time out it ran like a dream and when I went back into the marina it stalled out and wouldn't turn over. The guy I bought the boat off of shared he had issues with starter in the past and had been replacing it about every two years. I spoke to him today and he shared that a mechanic friend took the marine parts off the previous starter and sealed it.

When I took the starter up to the marina the guy there sold me an API Marine 10099HD starter which is half the size of the starter that was in there. When we installed it, the starter didn't sound like it was lining up with the flywheel. I believe the guy at the marina sold me the incorrect starter, even though he swears that should work. The number I found on the block was (1023878), when I searched, it turned out to be an 1996-1997 OMC 305.

Any idea on what type of starter this engine takes?

Thanks,

Andy
 
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Bt Doctur said:
that starter is a direct replacement, did the old starter just quit or was it making the same sound?
Click to expand...


Thank you for the reply - I personally didn't have a chance to hear the engine turn over with the new starter because I was at work. My uncle said it sounded like the flywheel wasn't matching up with the gears in the starter.

I wanted to share a little more information about what happened -- The motor ended up stalling when I switched it from reverse to drive. When I went to restart, it cranked over a few times and just seized up -- Looking back it was almost like the battery had died. I immediately went to the back of the boat and switched to the second battery and it did the same thing. They are older battery's and looking back I should have probably put a charger on them before messing with the starter.

That being said, when we got home, we immediately took the starter out. The starter was so hot that it ended up putting a nice burn on my uncle's hand. I spoke with the person I purchased the boat from last night and he shared that he had the spark plugs get fouled up one time when he had the boat and it wouldn't turn over. He took the spark plugs out and cleaned them up and it worked just fine. He did say those plugs were changed last year though.

I'm really hoping I don't need to take it to the marina to figure out what the issue is. If anyone has ideas, I am open to suggestions.

Thanks again,

Andy
 
Thank you for the reply - I personally didn't have a chance to hear the engine turn over with the new starter because I was at work. My uncle said it sounded like the flywheel wasn't matching up with the gears in the starter.

I wanted to share a little more information about what happened -- The motor ended up stalling when I switched it from reverse to drive. When I went to restart, it cranked over a few times and just seized up -- Looking back it was almost like the battery had died. I immediately went to the back of the boat and switched to the second battery and it did the same thing. They are older battery's and looking back I should have probably put a charger on them before messing with the starter.

That being said, when we got home, we immediately took the starter out. The starter was so hot that it ended up putting a nice burn on my uncle's hand. I spoke with the person I purchased the boat from last night and he shared that he had the spark plugs get fouled up one time when he had the boat and it wouldn't turn over. He took the spark plugs out and cleaned them up and it worked just fine. He did say those plugs were changed last year though.

I'm really hoping I don't need to take it to the marina to figure out what the issue is. If anyone has ideas, I am open to suggestions.

Thanks again,

Andy
 
Bt Doctur said:
that starter is a direct replacement, did the old starter just quit or was it making the same sound?
Click to expand...


Thank you for the reply - I personally didn't have a chance to hear the engine turn over with the new starter because I was at work. My uncle said it sounded like the flywheel wasn't matching up with the gears in the starter.

I wanted to share a little more information about what happened -- The motor ended up stalling when I switched it from reverse to drive. When I went to restart, it cranked over a few times and just seized up -- Looking back it was almost like the battery had died. I immediately went to the back of the boat and switched to the second battery and it did the same thing. They are older battery's and looking back I should have probably put a charger on them before messing with the starter.

That being said, when we got home, we immediately took the starter out. The starter was so hot that it ended up putting a nice burn on my uncle's hand. I spoke with the person I purchased the boat from last night and he shared that he had the spark plugs get fouled up one time when he had the boat and it wouldn't turn over. He took the spark plugs out and cleaned them up and it worked just fine. He did say those plugs were changed last year though.

I'm really hoping I don't need to take it to the marina to figure out what the issue is. If anyone has ideas, I am open to suggestions.

Thanks again,

Andy
 
Andy, with any SBC engine (car, truck or marine), the flywheel ring gear tooth count determines which starter motor is to used.

the 153 tooth will always use the starter motor with the straight across bolt pattern.
the 168 tooth will always use the starter motor with the staggered bolt pattern.

You will see the HTGR/PMGR starter motors as replacements. These are generally good. Especially the ones with all steel reduction gears!
You will also see the old school Non-Gear Reduction motors that by today's standards are pretty much out-dated and should NOT be used!


Do not let the pinion gear tooth count confuse you.
The flywheel ring gear tooth count is what you will be concerned with!


Make sure that you receive NEW bolts with the new starter motor!
(each brand HTGR/PMGR starter motors will have a unique nose housing casting)
Because of this, the mounting bolt length may become unique to this certain manufacturer.
In other words, use caution so that the specially knurled bolts will not bottom out prior to fully clamping the nose housing to the engine block.
Likewise, make sure that the bolts are long enough!



.
 
Thank you for the reply - I personally didn't have a chance to hear the engine turn over with the new starter because I was at work. My uncle said it sounded like the flywheel wasn't matching up with the gears in the starter. I just want to make sure this is the correct starter before I tear up my flywheel too and have to pull the entire engine out.

I wanted to share a little more information about what happened -- The motor ended up stalling when I switched it from reverse to drive. When I went to restart, it cranked over a few times and just seized up -- Looking back it was almost like the battery had died. I immediately went to the back of the boat and switched to the second battery and it did the same thing. They are older battery's and looking back I should have probably put a charger on them before messing with the starter.

That being said, when we got home, we immediately took the starter out. The starter was so hot that it ended up putting a nice burn on my uncle's hand. I spoke with the person I purchased the boat from last night and he shared that he had the spark plugs get fouled up one time when he had the boat and it wouldn't turn over. He took the spark plugs out and cleaned them up and it worked just fine. He did say those plugs were changed last year though. My next best guess is that there is some sort of short or the starter is not drawing enough amps to work properly. I'm going to troubleshoot that this evening and see what happens.

I'm really hoping I don't need to take it to the marina to figure out what the issue is. If anyone has ideas, I am open to suggestions.

Thanks again,

Andy
 
Andy, make sure that the Engine did not pull water back into the cylinders.
If water entered even a few cylinders, it would cause what some refer to as a Hydro-Lock (since liquids resist compression).
A Hydro-Lock cannot be over-come by any starter motor, and it would certainly cause the starter motor to over-heat.

I would remove all spark plugs and get it turning over ASAP.


********************

Back to the starter motor.
The OMC GM SBC Engine commonly used the 168 tooth ring gear flywheel. (early Volvo Penta used the 153 tooth)
If your old starter motor used the staggered Bolt Pattern, your new HTGR/PMGR starter motor will also use the staggered bolt pattern.

Some advertise 9 tooth pinion and/or 11 tooth pinion.
Don't be confused by this!
The nose housing and center of armature accounts for the differences.




.
 
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I have been working on the boat all day.

You were correct, there was water in the cylinders. I also tried to take off the outdrive and it wouldn't budge. I even loosened the engine mounts and lifted it a little with a fork lift and still no luck.

Does anyone have any ideas why I'm getting water into the cylinders?
 
I don't know why my reply was posted so many times - We ended up draining the cylinders and it started right up. I have made three trips on it since without any issues, but this last time it ended up hydrolocking again. We trolled for about two hours and it stalled out - we turned her over and I immediately knew that it had water in the cylinders again.

We were able to pull the plugs and turn her over - after a couple of attempts and a little starter spray, it fired right up and got us in.


I am familiar with car motors, but boats are new for me. The last time it hydrolocked it was because I went from drive to reverse quickly because a boat cut in front of me while I was heading into the dock. I didn't have any water in the engine well, so I my guess is it has to be something on the outdrive??? Again, I have no idea about boat engines and any direction would be helpful.
 
DO NOT...... repeat.... DO NOT put this engine away wet.

While at home and on the trailer, disable the seawater pump.
It looks like your engine still has the ESA system attached, so your drive will be OMC.
Your seawater pump will be within the upper gear unit.

Once disabled, give the engine a 10 or 15 second "dry start" as to blow any water out of the cylinders.
Do it twice if need be!
You will not harm anything in this short duration.


Now..... in post #1 you mention a 1987 Bayliner, of which would have been OEM with the OMC Cobra stern drive.
Later in post #1, you mention that the engine turned out to be an 1996-1997 OMC 305.
By 1996 or 1997, OMC was no longer a company due to chapter 11 and the eventual Volvo Penta purchase.
Any thought-to-be OMC engine/stern drive after 1993 would be the new version Volvo Penta Cone-Clutch SX or DP-S .





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I pulled this serial number off the block of the engine: 10243878 -- That puts at least the block as a 1996-1997 Chevy 305 small block. It still has the original outdrive (MOD. NO. 984541) on it. Do you have any suggestions on why I continue to get water in the cylinders? It doesn't happen every time I am out, but seems to get in there when I run it at idle for extended periods of time or move from drive to reverse too quickly.

I will make sure it is completely dried out after work today.
 
Ayuh,.... The usual culprits are the gaskets fail, 'tween the manifold, 'n riser,...

Or, after an overheat, the exhaust shutters are all burnt up, 'n allow back wash in,....
 
I agree with Bill.

With the engine warmed up, crack the bolts that secure the Elbow to the Manifold.
Finish the job when things cool back down.


Inside of this area will be the main exhaust gas chamber.
Around the perimeter of this area will be the "seawater transfer" ports.
The cast iron material must be in good condition, and the gasket must keep these two areas separated.

Post photos...... we can better help you if we can see how these areas look.


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