Tar? on Pistons?

[bhpjon]

Evenin' all, in the process of dismantling my engine and what appears to be a Tar like substance on the pistons, it's not just carbon (i don't think) and it is a bugger to get off even with a wire brush and petrol. My thought was oil being burnt but then i only use the finest Mobil 1 5/50 (obviously i can't guarantee what has been used throughout it's tvr service history life before me) and previous engines have only had the carbon deposits on which have come off quite easily, there was some oily residue in the intake manifolds and trumpets (from crankcase breather) but this seeems most odd? any ideas?

[bhpjon]

Quinny said:

Just left them soaking in a parafin bath for a day or so. Then used a stiff nylon brush to remove the deposits

Before


After

So do you know if this is normal?

[bhpjon]

Quinny said:

Haven't seen your pistons, but if they look anything like mine before cleaning, then yes I'd say that was pretty normal.

Cheers, if i knew how to post photos, i would ,but yes they were just worse than yours, what kind of milage has yours done incidentally?

[CaptiV8ed]

I'm in the midst of changing my cam and got the heads off last night. My engine has done 39k and the piston crowns are as Quinny's. I've taken off many a cylinder head off in my time from a range of engines and they all have appeared like this! So I would say perfectly normal.

Note for Quinny, your engine rebuild site is flippin' marvellous! It gave me a great understanding of what to expect when pully my V8 to bits and when my new cam goes in, I'm now armed with a good base knowledge of timing it in. Very well done Sir!

[chrispitman]

Quinny - Whats the web address of you engine rebuild as just starting on mine.

[bhpjon]

Quinny said:

40k at the time of the rebuild

Same as mine, excellent, thanks very much, incidentally are you putting a Stealth cam in ?

[CaptiV8ed]

I'm going for the stealth.

[andy-w]

hmmmm...the north east seems to be filling up with TVR's in various states of stipdown....

I feel left out...think i shall finish my can and go and start on my stipdown...

[That Daddy]

Years ago piston crowns used to be a nice biscuit brown colour(if all was well) but since the demise of 4star leaded fuel most engine internals are black in colour(just like this one)on the same leaded 4 star if you ran an engine hard the tail pipes would be grey in colour and chambers brown,unleaded burns differently so the best you can see in the combustion chambers is grey exhaust valves and black tailpipes

[bhpjon]

CaptiV8ed said:

I'm going for the stealth.

Are you fitting it yourself may i ask?

[bhpjon]

andy-w said:

hmmmm...the north east seems to be filling up with TVR's in various states of stipdown....

I feel left out...think i shall finish my can and go and start on my stipdown...

I think i would work on your keyboard first Andy, the 'r' is a bit hit and miss! No seriously engine is dismantled so i'm now trying to find all the new bits to go back in! Are you 'Stealthing' by the way?

[ray_von]

bhpjon said:

andy-w said:

hmmmm...the north east seems to be filling up with TVR's in various states of stipdown....

I feel left out...think i shall finish my can and go and start on my stipdown...

I think i would work on your keyboard first Andy, the 'r' is a bit hit and miss! No seriously engine is dismantled so i'm now trying to find all the new bits to go back in! Are you 'Stealthing' by the way?

Didn't know he was doing the cam. My opinion is leave it if its ok, but thats just me

[bhpjon]

ray_von said:

bhpjon said:

andy-w said:

hmmmm...the north east seems to be filling up with TVR's in various states of stipdown....

I feel left out...think i shall finish my can and go and start on my stipdown...

I think i would work on your keyboard first Andy, the 'r' is a bit hit and miss! No seriously engine is dismantled so i'm now trying to find all the new bits to go back in! Are you 'Stealthing' by the way?

Didn't know he was doing the cam. My opinion is leave it if its ok, but thats just me

Ray von were you one of the team of 'body lifters' by any chance?

[CaptiV8ed]

bhpjon said:

CaptiV8ed said:

I'm going for the stealth.

Are you fitting it yourself may i ask?

Yep! At the mo it's all stripped, cleaned and ready to go, but my stealth kit hasn't turned up yet. V8D are out of valve springs they tell me. I'm doing it the old way, ie heads off, good clean up, relap valves. While I'm there and there's room to move, I'm sorting the chassis a bit too. I intend to take the top wishbones and dampers out of their brackets, needle gun it back to clean metal and prime/paint. Hopefully, when all back together, it should look nice and blingy too!

[MrFlibbles]

Quinny said:

chrispitman said:

Quinny - Whats the web address of you engine rebuild as just starting on mine.

Thanks folks I knew it'd come in usefull one day

http://interweb4u.com/griff500

I spent a fair while reading all that yesterday

Very interesting for someone who doesnt know his conrod from his piston ring.

[ray_von]

bhpjon said:

Ray von were you one of the team of 'body lifters' by any chance?

No mate,sorry. Too many cooks and all that plus I'm lazy

[andy-w]

ray_von said:

bhpjon said:

Ray von were you one of the team of 'body lifters' by any chance?

No mate,sorry. Too many cooks and all that plus I'm lazy

... and there was strong chance of getting dirty hands...!!!

[andy-w]

CaptiV8ed said:

I intend to take the top wishbones and dampers out of their brackets, needle gun it back to clean metal and prime/paint.

Hope you dont find what i found when i removed my body...a very nice hole in between the lugs for the top front wishbone...not a very happy sight but fixed now.
Fingers crossed that yours is OK...!!!

Edited by andy-w on Sunday 22 April 19:50

[bhpjon]

CaptiV8ed said:

bhpjon said:

CaptiV8ed said:

I'm going for the stealth.

Are you fitting it yourself may i ask?

Yep! At the mo it's all stripped, cleaned and ready to go, but my stealth kit hasn't turned up yet. V8D are out of valve springs they tell me. I'm doing it the old way, ie heads off, good clean up, relap valves. While I'm there and there's room to move, I'm sorting the chassis a bit too. I intend to take the top wishbones and dampers out of their brackets, needle gun it back to clean metal and prime/paint. Hopefully, when all back together, it should look nice and blingy too!

Hi CaptiV8ed, YHM Cheers

[CaptiV8ed]

BHPJohn,

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