Starter/ompression?????????????

[Aliza]

Hi Guys Just want to thank everyone who has help this BELOW novice Jet boat owner in the past two weeks , But here is my problem the other day i was crusing down the river and my good engine which had a good compression or 150 across both cylinders
desided to shut off!! I tried starting it up but there was this horrible grinding sound , so i thought i had blown the engine! So i get home do a compression check and both cylinders are at 30psi,i take the engine out and while looking at the starter it looks completely trashed i desided to spin the shaft on the starter and sure nuff it made the crazy sound of bearings that hasnt been greased the exact sound as when i tried to turn the engine over!! So i get the engine completely out and i turn it by hand and it turns extremely smooth no bad grinding nor does it stick! my question is does anyone think that a bad starter would cause low compression being that the starter is the primary device for spinning everything?? and what should i do to confirm its the starter and not the engine now that i have everything out!!

 

[Seadoobuddy]

To ease your mind a bit..
I'm not the expert here but I think the starter only turns when starting the engine. So I don't think it has much to do with compression.

you said the "good engine"....were you running on only 1 of 2 engines at the time? Or is the second in bad shape too?

At 30 PSI no engine will run. I assume it made the same noise when you checked the compression.
Pull the plugs and using a wooden dowel or screwdrivers try to push the pistons up and down to see if it's seized.

Maybe the starter tried to spin the flywheel again and got mangled in the process???????
I would pull the head off and look inside and check the top of pistons.

Others will chime in shortly for better answers.

 

[Phildoo]

The starter could possibly not be spinning it over fast enough to get the compression. Like Seadoobuddy says, pull the head and look for catastrophic failure. If its ok looking I would drop it back in and a new starter.

 

[Aliza]

Thanks sea doo buddy for the response , good engine meaning the one with the best compression my other engine has a 150/140 split in compression! I am almost certain its the mangled starter that was making the noise and the cause of the low compression! i am taking off the good starter tomorrow and attaching it to the engine that i have out all ready and i am going to cover the carb holes to make a good seal and then i am going to run a compression check while the engine is out of the boat what every the results are i will share them with everyone! the starter turns the flywheel which turns the crank and i am guessing if the bearings or something else like a stripped output shaft is wrong with the starter it will not produce enough spin to make the pistons pump!! thanks again will let you know more tommorrow! I sure do hope i am right on this one! really do not want to spend a grand after just buying the boat a month ago!!LOL

 

[ocod]

Ouch.
You have been busy.

Just check compression again but I would pull head.

 

[Seadoobuddy]

If necessary for a new starter ..don't buy one off ebay. Lots of people have had bad results. I bought a *NEW* one from DBElectrical.com for around $50 for a Yamaha and it worked fine all summer.
OR you can get your rebuilt.

 

[Aliza]

Thanks Phildoo i scoped the heads also and i cant see anything out of the norm,I have spun it by hand and it spins very smooth! i will swop out starters tomorrow put the bad starter on the engine in the boat and put the good starter on the engine thats out and see if the same thing happens to the one that is still in the boat!! You guys are awesome I will keep you up to date!! Sweet Seadoobuddy thanks for the link ! you guys reply faster than i can type!! LOL

 

[Aliza]

OCOD My buddy where have you been!! when i get this thing running we need to meet up !!

 

[crisso]

Don't put a bad starter on a good motor .Get the bad starter looked at first.You said the motor you pulled out of the boat has only 30psi.how did you spin the motor to get that reading.That's not enough to blow the hat off your head.Maybe wait for the gurus to give their feedback.It may save a lot of time and effort

 

[Seadoobuddy]

Aliza - I agree with Crisso... Confucius says:"bad parts on a good motor may soon make for bad motor"...don't take the chance.
you said.... "looking at the starter it looks completely trashed" Take it apart to see or get it rebuilt first.

crisso...I assume he checked the compression while engine was still the boat. .......Was it a good gauge?

 

[crisso]

I doubt a bad starter could give a decent reading.Start at the beginning.Not halfway through.Ha ha Confucius didn't say that.you did.

 

[Gamerse]

I've bought two new starters from this guy for $60.00 shipped, no core needed.
http://stores.ebay.com/EMS-Global-Direct?_trksid=p4340.l2563
One is three years old now and spins the 1100zxi just like the first time, every time. The other is in my sportster. Prices have went up since then, they are closer to $100.00 shipped now. If the starter was stuck engaged, I'd trash it and get a new one.

:cheers:
Ernest

 

[Aliza]

Brand new compression gauge used! yes and it was the starter, the reason i put the starter on the other motor was to see if it would do the same thing and it did !! there is no way the starter could have done any damage to the other motor so i had to make 100% sure that it was the starter with the engine out and that was the only way to eliminate a blown motor by swopping out starters! Although i am new to boating i have 20 plus years on engine rebuilds of all sizes, so now that one engine is out its time to change all those filters and clean the bay really good!! thanks for the link again for the starters and I havent heard anyone say use the oem starters from sea doo why is that are the garbage or just to expensive? LOL

 

[Seadoobuddy]

OEM = $400 starter.

 

[Aliza]

OMG Sorry i even mentioned OEM i promise never to do that again!!!LOL

 

[ocod]

pm Minnetonka4me or his brother 99spxxx

 

[Seadoobuddy]

DBelectrical.com I bought one ($49) earlier this yr for my nephew Yama...works good so far.