Water In Oil Problems

[smithy 1]

These little cars definately test your patience..

 

engine is frshly rebuilt with new shells,gaskets and seals etc i also had liners out to hone and change the seals.I made sure the botoom of liners and the seat in block were spotless.

 

engine is running again with fresh oil in it has not been driven but i have had it running on drive for a total of about an hour.

 

the oil is all milky now the coolant had dropped by about a litre and half,to mix to such an extent in such a short space of time i think it can only be liner seals at fault. Long shot i know but anyone else think of anything that could cause the problem before i rip it apart again??

Also is there a way to 100% confirm liner seals when stripped down as i dont want to get it back together and find it is still doing it.

 

As for stripping it again would you do it in situ or get engine back out and do it on the stand?

[Pugs in Pieces 0]

more than likely be the liner seals, it didnt have an oil/water heat exchanger fitted did it? doubtfull but they can cause oil and water to mix too, the head was not badly pitted when putting it back together was it?

[Anthony 1,003]

Do I assume that the coolant is still clean and not also mayo'd? If so, that does indeed point the finger at something relating to the liner seals.

 

Whilst I'm sure it is possible to do in-car, given the ease of whipping an 8v engine out I'd be inclined to do that and do the job properly as you're really going to want to clean out as much of that mayo from the oil system as possible.

 

(as an aside, did you replace the rings when you rebuilt the engine? If so, leaving it running on the drive for an hour wasn't the best move as they need alternating load/vacuum to bed them in properly against the liners - just letting the engine run unloaded usually makes for a poor ring seal / compression / blow-by)

[smithy 1]

No heat exchanger fitted to this engine and head was in good condition with no pitting etc.

 

Did not change rings either I checked them and found in good condition so just honed liners.

 

Coolant is fine with no mixing in there and not pressurising it is just mixing in the sump.

Engine had previously frozen last winter and snapped belt,if it had also done damage to block I would think it would be obvious when stripped down?? Nothing looked amiss when on the stand.

 

Looks like it is coming out again tomorrow.

[Anthony 1,003]

Engine had previously frozen last winter and snapped belt,if it had also done damage to block I would think it would be obvious when stripped down?? Nothing looked amiss when on the stand.

That would concern me, as it could be a hairline crack somewhere that you've not spotted which only opens up / weeps when warm and/or the cooling system pressurises.

 

With it still in the car and the cooling system full, it might be worth dropping the sump off and leaving it overnight, see if there's any evidence of dripping/seepage to give you a clue - atleast that way you've potentially got an idea where it's leaking from, in case you take it apart and it's still not clear what's amiss.

 

A liner seal that you've nicked when fitting or hasn't quite seated right seems most likely though

[smithy 1]

sump off now i can see the area of concern is around no3 as the coolant has run down rear of block and pooled slightly on the lip on sump spacer.

I cannot see any coolant around the liner seat so i suspect as it cools down leak might stop or it is a slow leak (engine has been in and filled with fluids about 3 weeks so could have gradually filled sump)

 

unless there is a definitive spot where leak is in morning i think it might be a case of pressurising system and see what develops.

[smithy 1]

done a pressure test with a home made tester made out of length of hose,schrader valve and foot pump put 10psi in coolant was pumping out from no3 liner difficult to pinpoint exactly as it was running out by the main cap but i am 90% it is the seal and not cracked block.

 

engine back out just got to strip it and hopefully find a definate problem.

 

Tom fenton mentioned he used some non setting sealent on his just wondering what sealent is best to use?

[welshpug 1,666]

I think that may have been stag wellseal? used it myself on metal to metal joins and its great stuff, but not used it on liner seats

[mikeyd 13]

engineering firm that did the machining on my engine recommended bedding the liners/ seals with wellseal as it stays semi soft so wont crack/leak

[smithy 1]

thanks

 

i am going to get some when i put it back together dont fancy doing the job again should it leak still once back together.

[DamirGTI 344]

Myself , i always put a dab of copper sealant under and over the O-ring (Loctite copper sealant) .. and never ever had leaking problems with liners ..

 

Also , surface preparation is most important - block and liner O-ring seating surface ... needs to be well cleaned out of rusty/scale sediment , smoothed with fine grade sanding paper , surfaces spray cleaned with brake cleaner and then do the assembly job .

 

Damir

[smithy 1]

thanks for the info damir by copper sealent do you mean copper grease??

 

The liner and seat in block were well cleaned and rubbed down with 400grit wet and dry working up to 1200 to get nice and smooth,i am hoping i have either nicked the seal putting liner in or a bit or crap has somehow got under the seat at least then i will have a definite problem rather than hoping for the best?

[DamirGTI 344]

No , not the anti size copper grease , copper sealant .. this one :

http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_173139_langId_-1_categoryId_165691

 

Well , you'll need to strip the engine to detect the problem really ... The liner O-rings are a bit slim/delicate , so need to be careful not to twist them when fitting onto the liner or stretch them as they easy snap apart ..

 

Damir

[smithy 1]

thanks for clarifying that never heard of that stuff before thats what threw me going to strip it tomorrow,the seal went on liner well not twisted or snapped,they certainly are thin so easily damaged knowing my luck i probably caught it as i lowered the liner down in to block. Hopefully all will be revealed tomorrow morning.

[smithy 1]

Thankfully I have found a definitive cause,no3 liner seal in 2 pieces seat very clean so can only assume seal was twisted on liner slightly and got cut when clamping down head.

 

I will put a picture on later for those who are as sad as me and like to look at piccies

[Anthony 1,003]

Bit of a pain having to pull the engine apart again for something so simple, but atleast the cause is obvious and easy to resolve

[smithy 1]

Very true just glad it's not a cracked block,will have to be really careful when putting back together.

 

Last time I dropped liners in with pistons inside and the torqued big ends up,I reckon that was probably cause of problem so this time I am going to drop them in and put head on to clamp them down then torque up big ends. How does everyone else go about refitting to minimise the chance of damage to seals?

[smithy 1]

picture of the offending article