Riser hole (milky oil?)

[SavinRaven]

Would this hole in the riser sleeve cause milky oil? This is the only defect I could find in the riser or the manifold and where the leak down took me to..

 

[Bondo]

Ayuh,..... Welcome Aboard,..... What motor,..??
What vintage,..??

My 1st guess is Nope, but without the backstory, that's only a shot in the dark,....

 

[SavinRaven]

hello thanks for the welcome!
Thanks this is a mercruiser 1973 inline 6 165 250 ci. I did a aceton test on riser and it failed. welcomed! Last time we had it out it was overheating thought it was just impeller but long story short once I started investigating I found rotted transom so pulled motor and got itchy with it. This is only the second year we have owned it previously. Once motor was off noted exhaust bellows had gotten so hot that it had a hole in it and we had taken on about 3 gallons of water in the bilge. Also the exhaust boot that connect to riser was also melted. So lots of heat. Did white smoke. But started back up later once we got it home without issue. Now that transom is done working on reassembling gimbal and outdrive but I'm thinking now I may have bigger issues. After finding the milk I did leak down test no issues in cylinders but had air in the manifold area.. so I'm not sure I'm a bit clueless in this one

 

[SavinRaven]

Also gimbal bearing was shot from water. But that's unrelated

 

[Bondo]

Ayuh,..... Pressure test, Just the Block,......
A water leak into the exhaust has to leak/ seap down past the rings, to get to the oil,....
So, if the oil gets milky only when Not runnin',..... The exhaust could be the problem,......
If the oil gets milky when runnin', it's probably a cracked block,....

The burnt up rubber says it was run, with No water circulatin',.... at All,....

 

[SavinRaven]

So if it was running and the water was leaking from the riser into the air side of the exhaust it wouldn't make its way to the oil is what your saying? I will work on pressure testing the block I am gonna need some tools for this one. Luckily I have 2 blocks. But I'm hoping nothings wrong with this one.

 

[Bondo]

So if it was running and the water was leaking from the riser into the air side of the exhaust it wouldn't make its way to the oil is what your saying? I will work on pressure testing the block I am gonna need some tools for this one. Luckily I have 2 blocks. But I'm hoping nothings wrong with this one.

Ayuh,.... The water will just go out with the exhaust gases, when runnin',.....

 

[achris]

Three words to fear now that you've run without water... Water Pocket Cover.

Chris.....

 

[SavinRaven]

How would I check this I actually have a post about this on tht everyone said not to worry about it....

 

[achris]

How would I check this I actually have a post about this on tht everyone said not to worry about it....

No, worry about it. If the plastic cover has seen heat, it'll be distorted and will allow exhaust gases back into the cooling water, leading to an engine running hot...

 

[achris]

A few years ago I did a big write up on that cover and how to check it. Since the forum software change I've been unable to find it. Give me a while and I'll do it again. I'll put a link to it here...

Chris...

 

[SavinRaven]

hi Chris great! I appreciate it. Either way the parts seem cheap is it just really unexcesible? It seems like just a few bolts unless I'm missing something.

 

[achris]

hi Chris great! I appreciate it. Either way the parts seem cheap is it just really unexcesible? It seems like just a few bolts unless I'm missing something.

Here it is....

Water pocket cover - the how, the why and the what.

WATER POCKET COVER. What is it, where is it and why is it important. The water pocket cover is located in the bottom of the drive shaft housing, at the top of the exhaust cavity, of all MC-1, R, MR and Alpha One drives. It’s a plastic cover that has the copper tube from the water pump going...

forums.iboats.com

 

[SavinRaven]

going to pull the head today as i have a newly machined head i picked up a few weeks ago (For no reason other then it was cheap) So I will swap those out with new gaskets and check for any noticeable signs of wear. I will be sure to take plenty of pictures and post my findings.

 

[SavinRaven]

.
I expected to see a lot more damage then this. Yes frothy white milk was on top. But unsure what to do new gasket will be here by weeks end.. I guess put it in and see what happens.

 

[SavinRaven]

This is the most questionable spot in my mind but let me know what you guys think. Could the issue be deeper in the block? Or could this have had caused it?

 

[SavinRaven]

One other thing to note when I took a flashlight and looked inside the block I saw water but not a lot. I didn't see oil on the water side though... not sure if that means anything or not.

 

[SavinRaven]

got a quote of 2500$ to rebuild engine with new core.. I dont think thats a terrible price. Going to check a few other places today

 

[SavinRaven]

Hey all just to keep you updated on my story going on here: the guy that will probably eventually rebuild it said he wouldn't use the gaskets I have so in one last ditch attempt I am going to put on a reman head and gaskets with new oil and see where that takes me. So with that I tested the manifold today since the riser was already done. The manifold was toast to... so now i have to order that probably another 3 weeks plus out at this point on parts. I'll keep everyone up to date as it progresses...