Heads Off Due To Pressurised Coolant

[maxstu]

Removed both heads (spare engine) due to coolant getting pressurised and overflowing the top up canister.
Before deciding to remove engine l did the usual checks.
Bleed system about 15 times.
Checked blue cap. Quack quack.
So decided to play mechanic this week.
So what am l looking for?
Left bank 3 & 4

Right bank 1 & 2


Regards
Stuart

[Mocki]

Many years ago I had the same symptoms, I couldn’t bleed it , it just kept pressurising , when we took the heads off we found tiny holes between the combustion chamber and the coolant channels 







worth a close look... 

[937carrera]

Well, numbers 1 and 2 look cleaner, so I would say that is where the steam cleaning has been taking place.

Do you also see the rusty deposits on the bottom of the combustion chamber seal

Give them a clean with diesel / plus gas / some other solvent and look for cracks between the valve seats. I can't see any immediate issue for you though.

Did you do a compression test to see if the piston rings were in good condition, or are you going to replace them while it's out anyway (good idea )

[maxstu]

Called it day now. Thanks for answers. Will resume tomorrow with a good clean. Didnt want to disturb any evidence until you good lot took a peek.
On left bank noticed this. But cant see how it would affect coolant?

[300CE]

I can’t see anything jumping out there Stu - post a few pics up once they’ve had a good old clean up.

Have you got some Hylomar AF to put on the fire rings when you replace them mate?

[maxstu]

I can’t see anything jumping out there Stu - post a few pics up once they’ve had a good old clean up.

Have you got some Hylomar AF to put on the fire rings when you replace them mate?

Hi Justin,
Hylomar AF? I think l have somewhere. Will bathroom sealant do instead

I will give both heads a really good scrutiny tomorrow and post again. Yet not a sign of any cracking between valves. In fact the valve train area on both sides look in excellent condition. Just a bit grubby.

Main concern is why there was additional sealant around the lower sleeve black seals on both sides? And how comes this is 2.1 but has no oil pressure hole by pulley . And how to get round this with 1989 DOPs system?

[maxstu]

Home made puller for removing gudgeon pins. Forget what Haynes manual says about using a bit of hooked wire. Laughable



Remove one circlip (get the proper circlip pliers) from the side of piston you intend to drive out the pin. Then using a piece of threaded rod with a nut locked one end to catch against edge of gudgeon pin and a block of wood will do the trick. A bit slow but sure. Make sure nut doesnt foul against the other circlip though. You can feel its good to go with your finger. I think a M8 size works
Not sure about using a slide hammer as lve seen on some videos.

[937carrera]

Main concern is why there was additional sealant around the lower sleeve black seals on both sides? And how comes this is 2.1 but has no oil pressure hole by pulley . And how to get round this with 1989 DOPs system?

Looks like it's an early DG case with 2.1 barrels / pistons and a bit of machining to allow the components to clear.

If you put this in the van they just earth the rear connector and DOPS will be happy

[maxstu]

Well that sounds easy. Cheers David. Have seen PM too. Will answer tomorrow.
Will check cases for early/late signs.
Regards
Stuart

[937carrera]

It's a while since I have seen a WBX rebuild thread and I started thinking about how early an early DG could be.

Are you sure it's a 2.1. Those aren't DJ pistons, I suppose they could be MV, but after looking here https://www.volkszone.com/VZi/showthread.php?t=1278297 I don't think so.

They do look like DG pistons though.... cc checks at https://club8090.co.uk/forum/viewtopic.php?f=12&t=149884

[maxstu]

Well l did a stroke test some months ago and they measured 2.1. MV Or DJ lm now uncertain
MV


Whatever is in this engine. Look DJ to me

[937carrera]

From the links:

DJ's have a dome in the middle

MV's have the deep dish

DG has neither which is what I see in your picture.

I don't want be be unduly pessimistic, but can you measure the compression height ? (gudgeon pin to top of piston)

[maxstu]

From the links:

DJ's have a dome in the middle

MV's have the deep dish

DG has neither which is what I see in your picture.


I don't want be be unduly pessimistic, but can you measure the compression height ? (gudgeon pin to top of piston)

Will do tomorrow. Enjoying a large whisky at present.
I thought MV were domed not dished?

[weimarbus]

Sorry Stu, look like DG pistons to me, flat at bottom of dish, DJ has a small diameter raised dome in the middle, see shiney new. MV pisons have large diameter raised dome. MV seems counter intuitive, lower compression appears to have smaller chamber.
One of 'Silverbullets' build posts had more detail, but it was a while ago and may now be gone given photoshop issues.

[maxstu]

Cheers Andrew. It more a case of interest than disillusionment to be honest. Especially as the case number was altered to read DJ.
I started a post about this some months back before disassembling engine. I measured stroke too. And it matched the manual dimensions for DJ.
Will head back to garage shortly and start checking.
Regards
Stuart