Volvo Penta 4.3 GL Oil leak

[Flysooner9]

I have a 1999 Glastron 185 with the 4.3 GL in it. The engine was replaced 2 years ago, this is our first season with the boat. Everything runs fantastically except there is a pretty good oil leak coming from the rear port side of the engine towards the bottom. My first guesses would be wither pan gasket or main seal leaking but was wondering if there could be any other culprits. Its leaking about a quart or so a weekend (6-8 hours of run time). We are hoping to be able to put off pulling the motor till the fall as everything else is running fine. Only other idea is that maybe the pan bolts weren't torqued correctly on the new motor before we got it.

just to add to it, the most oil is found just aft of where the dip stick enters the pan, however i dont think its coming from that connection.

 

[further]

Try to use one of those foldable mirrors on a rod to locate where the oil is coming from if you can. I found mine was leaking where the dipstick connects at the oil pan.

 

[Flysooner9]

Not coming from the dip stick area but just another inch aft or so. There's a hole back in that corner that i can stick my finger up into and thats where the most oil is located, im almost fully convinced its the main seal at this point.

 

[Bondo]

I have a 1999 Glastron 185 with the 4.3 GL in it. The engine was replaced 2 years ago, this is our first season with the boat. Everything runs fantastically except there is a pretty good oil leak coming from the rear port side of the engine towards the bottom. My first guesses would be wither pan gasket or main seal leaking but was wondering if there could be any other culprits. Its leaking about a quart or so a weekend (6-8 hours of run time). We are hoping to be able to put off pulling the motor till the fall as everything else is running fine. Only other idea is that maybe the pan bolts weren't torqued correctly on the new motor before we got it.

just to add to it, the most oil is found just aft of where the dip stick enters the pan, however i dont think its coming from that connection.

Ayuh,..... That's where the oil filter boss is, I'd look there 1st,....

 

[lonewolf41]

I was going to say filter as well. Make sure on old o-ring/seal didn't get left behind on the block from an old filter. On my last oil change, the seal came off the filter and stayed on the block. Luckily, I checked it and found it before installing the new one.

HIH,
-Keith

 

[Flysooner9]

Filter area is completely dry as well.

 

[Flysooner9]

still stumped on this one, does anyone have any other ideas? Really want to make sure its a rear main before i go to the effort of pulling the motor. I've been told its very rare for those to leak especially on a 2 year old motor. Someone at the lake mentioned a manifold gasket but it seems dry.

 

[dypcdiver]

Use a camera or phone to get a picture/video whilst the motor is running, then check on a computer screen to get a better idea where it is leaking.

 

[Flysooner9]

So last season we found the oil was dripping from a hole on either side of the bell housing. After consulting with a shop they agreed it was the rear main seal.

Well this winter we pulled the motor and replaced the rear main seal as well as the oil pan seal. We started it up today for the first time this spring and I'll be danged oil is still dripping at the exact same location at the same rate. My dad and I are at a loss for ideas. Can anyone help with other ideas?

 

[Flysooner9]

ok so i would like to resurface this thread as we are about to pull the motor yet again. We ran it last season with the leak but of course want to get to the bottom of it before this next season starts. Is there a chance when the motor was manufactured before we bought the boat that they did a poor job and milled something out of spec thus causing a poor seal?.

 

[GA_Boater]

Do you know if this motor has a one piece rear seal? I think some do and some don't depending on which year and model.

The reason for the question is if it has a two piece seal, less tear down is needed to replace the two halves and the flywheel does not need to be removed to replace the rear seal. Behind the flywheel there are several core plugs and threaded plugs with pressurized oil on the other side from drilling oil ways and machining for the camshaft and if it has one, the balance shaft.

Remove the flywheel and look for signs of oil drips. Even with a one piece rear seal, I would do the check since a new seal made no difference.

 

[Flysooner9]

Yes it's a one peace seal. We're pretty confident it's still the rear main as there's evidence of oil leaking from the seal once the fly wheel is off. Just don't know why the seal isn't sealing correctly.