So this is what caused my breakdown

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bjmullan
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Post by bjmullan »

Guys I could do with a nice freshly build 2.0L engine....willing to pay the postage & packaging :lol:

That's the DDK spirt 8)
Brendan
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fourteener
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Post by fourteener »

Sorry to hear about the engine James, that's really bad luck. How did Barrel #6 get damaged? I thought maybe #4 might have caught some shrapnel as it's directly opposite.
James.

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Gary71
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Post by Gary71 »

This is real bad luck :cry:

But good to see the DDK spirit to the rescue!

oh and I could do with a set of 2.4E barrels, pistons and cams if anyone has some lying around :lol: :lol: :lol:
58A - 71E
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Post by 58A - 71E »

Thanks for all the offers of help guys :)

James (fourteener) - sorry, typo, meant to say cylinder number 4 :oops: it did indeed cop for the shrapnel

Barry - yes an inlet valve seems unusual, not sure if the valve guide has got stuck / failed somehow? also noticed that cylinder number 1 is dated 11/70 whereas the others are all 12/70, not sure if coincidence but maybe it has been replaced previously? I think I'll be speaking to JohnM's apprentice in Kendal Re the conrods :wink:
Barry you have a PM following Chris' generous offer, and as for loosing time, well, I thought I'd crack on

Image

This is what I've fished out so far

Image

Just putting the shopping list together now :roll:

Alan you have PM
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Indeed - gotta love DDK 8) :) 8)
James

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'71 911E 2,2


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butzsi
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Post by butzsi »

Guys I could do with a nice freshly build 2.0L engine....willing to pay the postage & packaging
Brendan, Sorry only a 3.0 RSR available - postage approx £9.56 plus vat !

Chris
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Post by Alan @ CanfordClassics »

Sorry only a 3.0 RSR available - postage approx £9.56 plus vat
:lol: :lol: :lol:
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Post by Gary71 »

I love to see this pace of work, nothing like just accepting it's got to be done and cracking on into it 8)
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bjmullan
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Post by bjmullan »

That a shame Chris about the RSR engine but I have a mint T and with all these recreations it's now becoming a rare model :lol:

I could of course dump all the MFI, slide valves and twin spark thingys and put my trusted Zenith on.....
Brendan
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Post by 210bhp »

bjmullan wrote:That a shame Chris about the RSR engine but I have a mint T and with all these recreations it's now becoming a rare model :lol:

I could of course dump all the MFI, slide valves and twin spark thingys and put my trusted Zenith on.....
Brendan
Just put the rsr stuff in a box after you mount the Zeniths and I will take them. Willing to pay postage of course.

Regards
Mike
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58A - 71E
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Post by 58A - 71E »

So I did a bit more investigating today as I really want to get to the bottom of why the inlet valve dropped...

I always wondered why, after adjusting the rocker clearances as accurately as I could why the engine still sounded tappety - well it turns out that my valve guides are well and truly sh*gged so the noise was in fact my valves bouncing around :roll: and then I turned my attention to the timing chains.
I replaced the tensioners with new 930 types and when the engine detonated these were the first things I checked. Unfortuntately, when I replaced the tensioners and chains I did not split the case and therefore inspect the Intermediate gears - well I probably should have done given how badly damaged/worn everything else was - especially as some numpty had installed the cam pulleys in the wrong way round - consequently this shouldnt have been a surprise

Image

Top 3 teeth missing and rest nearly ground away

Image

Difficult to see in the photo - but basically the chain has made a good job of completely knacking all the intermediate shaft cogs. So, it looks like the chain probably did cause the detonation by jumping , but not because of the usual chain tensioner failure, more because I didnt replace the intermediate gears to save splitting the case :evil: I reckon anyone replacing their slack chains should check their cam pulleys AND intermediate shaft pulleys at the same time. I wish I'd split the case then :roll:
James

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Matt black70
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Post by Matt black70 »

Glad to see you've found the root cause so it won't happen again, your findings could also save somebody elses engine in the future . Is there a way of checking play/ backlash without stripping the case?
I hope the rebuild goes well.
Regards
Matt
Last edited by Matt black70 on Fri Jan 25, 2008 12:11 am, edited 1 time in total.
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bjmullan
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Post by bjmullan »

Well at least now James you know the reason, and it's a good lesson for us all to learn. BTW you really didn't take long to strip that baby.
Brendan
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Post by Gary71 »

It's a real shame you are doing all this learning for us, but I will certainly take your advice and try to get a good look at the intermediate gears when I do my chains this week.

I feel a sympathetic pain in the wallet for you :cry:
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Post by hot66 »

are you going to replace the aluminium gear with a later steel one?
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58A - 71E
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Post by 58A - 71E »

James, I've already replaced all 3 cogs with original types, a bloke in Kendal :wink: had some lying around with no wear on, I'll replace the chains again at the same time and hopefully they should last better!
James

'58 356A 1600n
'71 911E 2,2


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