Technical JTD engine replacement saga!

[Hellcat]

re: JTD - Now my replacement engine has died!!!

How long has the new one been in? Sounds a lot like when my Tipo went. Have you been able to check on the tension of the belt?

 

[stilosporting]

re: JTD - Now my replacement engine has died!!!

no not yet. its been in around 3 months and driving around 6 weeks. maybe a thousand miles.

 

[Hellcat]

re: JTD - Now my replacement engine has died!!!

Mine was 11 months and probably around a thousand miles when the loose tensioner moved and the belt jumped.

Here's to hoping it's something else, or your valves aren't bent.

 

[stilosporting]

re: JTD - Now my replacement engine has died!!!

its definitely not doing a full turn due to contact. so i think its a case of how much damage the contact has caused.

 

[Big Black Stilo]

re: JTD - Now my replacement engine has died!!!

You should be able to tell if any valves are bent by just removing the camcover and checking for excessive clearances. Usually you'll find one or more buckets and shims cracked too.

but as well as ******ed valves need to check what, if any damage done to pistons

 

[D4nny8oy]

re: JTD - Now my replacement engine has died!!!

Piston's are fairly strong, but the point of my post was a quick and easy way to check and confirm for bent valves without removing the head.

Valve-guide damage is possible, other parts like the cam will probably look ok but you'll always have that nagging doubt about their longevity, so it may turn-out cheaper to get a replacement/exchange head.

 

[Big Black Stilo]

re: JTD - Now my replacement engine has died!!!

i saw a damaged piston recently that was making a VW TDi smoke like a trouper, was caused by bits of metal being where they shouldnt

 

[Argonought]

re: JTD - Now my replacement engine has died!!!

It's actually surprising just how much damage a piston can take.

I dropped a valve in a VW GTi engine once which took quite a chunk out of the piston top

After just a head rebuild, it drove OK for years afterwards

 

[stilosporting]

re: JTD - Now my replacement engine has died!!!

ok so we finally got the head off and it aint good news.

took the can cover off and all looked well. then we got the head off and one of the valves has snapped off.

 

[Most Easterly Pandas]

re: JTD - Now my replacement engine has died!!!

ok so we finally got the head off and it aint good news.

took the can cover off and all looked well. then we got the head off and one of the valves has snapped off.

Ouch

 

[cris1117]

re: JTD - Now my replacement engine has died!!!

Hi All
Just a point I would add it’s not always the piston that’s damaged, I once had a vectra in for repair the cam belt had snapped and been repaired by a small back street mechanic.
The car was smoking and hunting checked the timing looked O.K, after a strip down turned out the con rod was bent not a lot but enough.

Good Luck

 

[Argonought]

Re: JTD - Now my replacement engine has died!!!

I'm speechless Frank

It is at least interesting to see the inside but I'd prefer not to see it in such a state.

ps updated thread title - just in case someone wants to donate another engine

 

[Adrian Bravo]

Re: JTD - Now my replacement engine has died!!!

blimey and i thought mine was bad. What was that cylinder bore like? Any pics?

Good look with it, do you have a plan?

 

[stilosporting]

Re: JTD - Now my replacement engine has died!!!

the bore is scored but only finely, you can see it but not feel it.

the aim is to replace the piston and get a new or 2nd hand head and rebuild her. if i can do it cheap enough i will give it a go. otherwise it is being sold on ebay 'as is'.

 

[stilosporting]

Re: JTD - Now my replacement engine has died!!!

Hi All
Just a point I would add it’s not always the piston that’s damaged, I once had a vectra in for repair the cam belt had snapped and been repaired by a small back street mechanic.
The car was smoking and hunting checked the timing looked O.K, after a strip down turned out the con rod was bent not a lot but enough.

Good Luck

i'm not too sure what you mean by this if you se the pictures it clearly shows the piston is fooked beyond repair.

 

[Argonought]

Re: JTD - Now my replacement engine has died!!!

So did you get to the bottom of why the new cam belt came adrift (I assume it didn't break :chin: ) ?

 

[stilosporting]

Re: JTD - Now my replacement engine has died!!!

So did you get to the bottom of why the new cam belt came adrift (I assume it didn't break :chin: ) ?

im not sure if it was the timing. that all looked correct and there was no play in it to suggest it skipped a tooth.

to be honest i have no idea what caused the valve to snap off.

 

[Adrian Bravo]

Re: JTD - Now my replacement engine has died!!!

See the valve to the far right, looks like its had a valve removing tool on it before.

 

[Argonought]

Re: JTD - Now my replacement engine has died!!!

im not sure if it was the timing. that all looked correct and there was no play in it to suggest it skipped a tooth.

to be honest i have no idea what caused the valve to snap off.

Sorry, got confused by your pictures and thought two cylinders were in the same state but now realize only one cylinder is damaged.

Something mighty weird has happened there

What does the supplier of the engine say about all this?

 

[cris1117]

Re: JTD - Now my replacement engine has died!!!

Hi All
Perhaps I should have been a little clearer, my previous comment was meant in general not to your particular problem.
Although by the amount of damage your piston has sustained I would be very cautious as to the condition of the con rod, it would be a shame to rebuild the engine and then discover the con rod is bent as happened to my client.
Out of interest has the valve stem become dethatched from the spring, have the collets come out and dropped the valve which has then been snapped by the piston or has it just snapped?
I can see the stem still in the shaft but this often happens when a valve is dropped the piston hits the valve pushing the stem back into the shaft then breaks the valve head off.
Looking again at your photos I would guess that the engine had previously sustained a cam belt failure and been repaired (hence the markings on the undamaged valve which may have been a replacement) and the valve that has dropped was either weakened but not bent and has now broken, or the valve that has dropped was also a replacement that has been incorrectly fitted.
Very bad luck!