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Discussion Starter · #1 ·
Took my car to brian in Chorley - engine is rumbling slightly as revs get to top end - crank probably. He said this sometimes happens. But it is expensive to fix. £1000 or so. Nightmare!
This is causing the boost to retard(due to knock sensor picking sound up). Questions:
1)Advised to fit a manual boost control - this will allow sustained boost?
2)Brian says I dont have to worry about crank - its not about to die - would fitting MBC be silly - will it reduce life drastically?
3)I can't afford new crank, or even s/h engine, would MBC be a wise choice? I tend to keep the car in good condition, and check everything weekly - or should I just live with the boost as it is?

Advice appreciated.
Cheers
 

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I would say put a MBC in and set it to a sensible level ie 13psi, use the torque of the engine not the revs and you should be ok for the foreseable future.
This will at least give you some time over the next few months to keep an eye out for that bargain secondhand engine to come up!!

Pete
 

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To be honest Paul, a crank can rumble indefinately, how are you sure its main bearings? and not just the big end shells?, if its the big end shells you ccould replace these yourself quite cheaply.
The other alternative is to change the oil to something slightly thicker say a 10w/40 to combat the enlarged clearances down below.
If its any consolation my old T16S engine went on knocking for ages before i got it replaced recently, it was doing exactly the same as yours was- knocking boost back due to the knock sensor picking up stray knock from the engine.
Dont worry to much!
Get that MBC in there!

Pete.
 

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Discussion Starter · #5 ·
Thanks Tandino - slightly reassured now!
I took it to a guy who was recommended here - took it for drive, came back and said boost was cutting back at top end (which i knew), he said cause was crank rumbling, as the engine got noticeably louder at high r3evs(i hadnt noticed it, and still don't - !) I trust him, 'cos he said he wouldn't recoomend repairing 'cos of cost, go find myself a s/h engine somewhere. He also said try a 15/40 oil, instead of 10/40 I have at mo. He also said it might even be balancer shafts - how could I be sure exactly what it is, and if it is repaiarable.
I'm off to buy a MBC tomorrow - will this stop the boost taper?
Cheers
 
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