? Big end faliure again!

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Althulas
Joined: Fri 13 Feb, 2009 00:55
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? Big end faliure again!

Post by Althulas »

Last Friday I noticed a slight tappet sound at the top of my engine. So I asked the Indy to take a look while doing my service and came back with he could only hear vanos noise but said to come back if I noticed any new unusual noise. Today the oil temp did rise quicker than normal on a short journey into town and noted the return of a very similar tapping knocking sound and went straight to my Indy who was outside on arrival and did not need to hear engine fired up again to give a diagnosis of most likely big end failure.

I have run the this engine in very carefully, had the conrod bolts replaced with ARP bolts which are supposed to be far superior to the oem ones and I have never redlined since the rebuild as I'm to cautious to after the last expensive engine rebuild, so at a loss as to why this would happen again.

The short engine rebuild was done by someone who my Indy sources out to and has never had any problems with any units he has done before. I pointed out that the engine was supposed to have a 2 year guarantee and I have only put about 10k on it post the running in period. So the Indy is going to take a look at it tomorrow and let me know the damage and will get onto the engine builder where we go from here if it is a worst case scenario as I said I can not justify another crank replacement etc out of my own pocket again.

Just needed a rant :shake:
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Joycey
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Re: ? Big end faliure again!

Post by Joycey »

Sorry to hear that mate. They are defiantly at fault unless they can prove a defective part. 10k after an engine rebuild is just not cricket.

Hope you get good news from them soon.

Lee
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Brian H
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Re: ? Big end faliure again!

Post by Brian H »

Sorry to read this…….again! hope it gets sorted for you.
Bi11
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Re: ? Big end faliure again!

Post by Bi11 »

Gutted for you. Fingers crossed you get it sorted under warranty.
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Southernboy
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Re: ? Big end faliure again!

Post by Southernboy »

Did you fit OEM white metal bearings at the last overhaul? Also, have a look at the oil pump, although if it's big ends, they shouldn't be able to run dry. If it's the small top piston bearings, that's another matter.
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Althulas
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Re: ? Big end faliure again!

Post by Althulas »

Properly should have continued from my old Fred Barry. I had a secondhand crank which was reground, polished and balanced with the conrods. New OEM +025 bearings and mains were fitted, the conrods secured with arp bolts. A new oil pump was fitted and new timing chain and tensioners.

Just waiting on the conformation of the diagnosis and hopefully covered by the warranty.
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Davejue1
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Re: ? Big end faliure again!

Post by Davejue1 »

Sorry to hear your having big troubles again. I remember you having the enine rebuild done. I hope they man up and honour there work. Good luck.
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stevov
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Re: ? Big end faliure again!

Post by stevov »

Personally would never recommend grinding crankshafts. Either new or a good second hand that measures in spec.
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Althulas
Joined: Fri 13 Feb, 2009 00:55
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Re: ? Big end faliure again!

Post by Althulas »

Well some good news of sorts. The builder of the short motor has a look at the garage request. At cold there was no noise to be detected but as the engine started to warm up and a quite knock was there as I informed so sump whipped off to find only number 6 bearing had started to wear. Fortunately no scoring to the crank and measured to parameters and no debrie found. Just awaiting for new shells to arrive from Germany. Cause unknown ? Manufacturing fault in shell, I did get asked about if it had run low on oil which I have anally kept an eye and have only used 100 or so ml after it's run in oil change. So just the monies to discuss when the job is done. Pity I'm off to the isle of Mann for the next 3 - 6 months early next week so going miss it for a little while oh and the wife if she happens to read this thread :)
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Southernboy
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Re: ? Big end faliure again!

Post by Southernboy »

Since the sump is off, has a comparative check been done on the diameter of the crank pin journals ? If # 6 is different - ie. measurably larger or smaller, this may account for the failure. Also, the shells should have the same part number engraved on the outer side - has this been checked with the other shells from an undamaged bearing. Possibility is one set may not have been correct from the supplier, or the journal wasn't finished to spec as was done one journals 1 to 5 at the time of the 1st overhaul.
You need to ask your mech to check the oil feed to that crank pin journal and bearing to ensure it is clear and adequate oil is feeding there too.



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gookah
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Re: ? Big end faliure again!

Post by gookah »

Althulas wrote:Cause unknown ? Manufacturing fault in shell,.....?
Althulas wrote: I pointed out that the engine was supposed to have a 2 year guarantee
Althulas wrote: So just the monies to discuss when the job is done.

Cracking guarantee then......?
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Althulas
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Re: ? Big end faliure again!

Post by Althulas »

Cheers Barry only trouble with posting a brief message but I did ask all those relevant questions as I was concerned and a bit ticked off after shelling out quite a lot of money and was informed that the crank had been machined to spec but I will ask about the shell part numbers. I have been going over the cause of this a lot lately but I cant find any fault of my own and only can remember driving while tired :dunce: and miss reading a bit of road and really hit a speed hump way to fast which resulting in me bouncing the front end of the car up and coming down heavy really woke up then properly unlikely.

Gookah I'll let you know all know when its done, the Indy didn't commit to a answer just said not to worry so don't know what's that's supposed to mean but find out soon enough I suppose.
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gookah
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Re: ? Big end faliure again!

Post by gookah »

Hope its all sorted with no expense.
I remember this post in January last year, linkyso you are less than 18 months in. 10,000 miles in 18 months is not a great amount and a rebuild should last well in excess of this.
Let him know that we are all watching the outcome of this, and are hoping he does the right thing..
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Althulas
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Re: ? Big end faliure again!

Post by Althulas »

I have come home for a short visit and collected my car, the builder of the bottom end can only put it down to a faulty bearing so I have only paid for parts. So nice to have a drive after 8/52 doing without.
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Bi11
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Re: ? Big end faliure again!

Post by Bi11 »

Glad you are back on the road again!
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Southernboy
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Re: ? Big end faliure again!

Post by Southernboy »

Congrats on getting the car back. Just take it easy on the bearings for 500km or so and then do another oil change. Yes, it is expensive, but the wear as the bearings seat in will be greatest at the outset, and you want to make sure you drain excess metal particles out. A BMW mech here tells me the best is to use the gears as a brake when slowing down as this pumps oil into the top of the motor without any being burnt off as would be under acceleration. The benefit is that the oil then drains down to the sump and "washes" any particles off the crank and into the sump.
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Althulas
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Re: ? Big end faliure again!

Post by Althulas »

Not going to get a chance to do many miles before I fly back to the IOM on Tuesday. Back again in September for the lads wedding and hopefully contract extension should be confirmed at the start of October being so my skill set is needed over there buy wait and see before ferrying my car over :drive She will be meticulously run in again and have another oil change as before and hopefully no more dramas with the engine.
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