Spun a big end bearing!
#1
Spun a big end bearing!
Noticed a slight knocking on the way back from Ford Fair and that my oil pressure was a little lower than normal at idle, just dropped the sump and checked the rods for play, No. 1 had some so off with the caps and I've spun a bearing! Checked No. 4 and thats fine as is it's journal, at this point I lost the will to live and have come in! lol
So looks like it's just No. 1 thats suffered, what would cause this?
Thanks!
There is no oil on the shells or cap in those pics, the discolouration is score marks and heat!
So looks like it's just No. 1 thats suffered, what would cause this?
Thanks!
There is no oil on the shells or cap in those pics, the discolouration is score marks and heat!
Last edited by Karlos G; 13-08-2011 at 04:15 PM.
#2
Shit thats awful news mate im really gutted for you. In my experience your clearance on no.1 was probably too tight. The bearing wears quickly and eventually (normally a little sooner than this)either causes an excessive clearance and improper lubrication, or excessive heat due to its tight clearance the bearing will have run hot enough to seize/close to seizing in a particular place and therefore spun.
High RPM for a long period (on the motor way) probably won't have helped, plus it can be very difficult to notice a loss of oil pressure fast enough to save anything.
Its a night mare, because as soon as the bearing moves your fucked (covers oiling hole) You see this with engines that have low oil pressure too.
If i can make a suggestion.
When you rebuild it really REALLY thoroughly measure clearances and match bearings to get in the middle of a stock ford range, I took quite a few pics with explanations in my build thread. Its more or less what people refer to as blue printing.
You will need some decent callipers for measuring, some plastigauge and A LOT of patience, my bottom end too over 10hours to measure up and build.
Have you got any pics of the inside of your bearings?
If you need any thing Karlos let me know, PS its a shame i didn't bump into you at FF i was on the look out for your car all day but didn't see it
Rob,
EDIT, noticed you already had a pic of the insides of the bearings, it has run very hot in places.
High RPM for a long period (on the motor way) probably won't have helped, plus it can be very difficult to notice a loss of oil pressure fast enough to save anything.
Its a night mare, because as soon as the bearing moves your fucked (covers oiling hole) You see this with engines that have low oil pressure too.
If i can make a suggestion.
When you rebuild it really REALLY thoroughly measure clearances and match bearings to get in the middle of a stock ford range, I took quite a few pics with explanations in my build thread. Its more or less what people refer to as blue printing.
You will need some decent callipers for measuring, some plastigauge and A LOT of patience, my bottom end too over 10hours to measure up and build.
Have you got any pics of the inside of your bearings?
If you need any thing Karlos let me know, PS its a shame i didn't bump into you at FF i was on the look out for your car all day but didn't see it
Rob,
EDIT, noticed you already had a pic of the insides of the bearings, it has run very hot in places.
Last edited by Rob_DOHC; 12-08-2011 at 10:29 AM.
#3
PS, from the pics it looks like your crank has got to come out, i couldn't tell you if the conrod was scrapped or not. If you just slap another bearing in i guarantee it will happen again.
Sounds like the perfect time to go to the dark side (zetec).
Rob,
Sounds like the perfect time to go to the dark side (zetec).
Rob,
#5
You should never oil the back of the bearing mate, especially if your plastigauging. But im sure karlos will have lubed the bearing face before build up.
Rob,
Rob,
Last edited by Rob_DOHC; 12-08-2011 at 02:32 PM.
#6
when my engine span a shell it was about 400 miles after the rebuild and i was still running it in
span it enough to ruin the crank and the bits went all through the engine so it was fooked
when you rebuild it make sure everything is cleaned out
span it enough to ruin the crank and the bits went all through the engine so it was fooked
when you rebuild it make sure everything is cleaned out
#7
exactly why I asked mate. common error made by many. on the merc truck engines I built they went in bone dry. then drop of oil on outer face on assembly.
Last edited by series_one_rst; 12-08-2011 at 02:53 PM.
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#8
#9
Yeah I'm gutted too mate, been running perfectly for over a year and 12000+ miles too!
I did think about ZT but cost is a big problem for me right now, just rebuilding the CVH will be Ł300-Ł400 I would need another Ł600 at least to ZT so it's not an option.
When I built it I didnt 'blue print' it but I will this time to to be sure, I'll also balance everything up too.
No I didnt lube the back of the bearing.
My magnetic sump plug has a fair 'afro' on it from the swarf so thankfully the rest of the engine is ok, the oil wasnt grey like it would normally be when a bearing fails.
But yes the crank now needs a grind as No. 1 journal is heavily scored.
Yeah It's a shame I didnt see you at FF, my car was on a stand to the left as you came in...
I did think about ZT but cost is a big problem for me right now, just rebuilding the CVH will be Ł300-Ł400 I would need another Ł600 at least to ZT so it's not an option.
When I built it I didnt 'blue print' it but I will this time to to be sure, I'll also balance everything up too.
No I didnt lube the back of the bearing.
My magnetic sump plug has a fair 'afro' on it from the swarf so thankfully the rest of the engine is ok, the oil wasnt grey like it would normally be when a bearing fails.
But yes the crank now needs a grind as No. 1 journal is heavily scored.
Yeah It's a shame I didnt see you at FF, my car was on a stand to the left as you came in...
Last edited by Karlos G; 12-08-2011 at 03:56 PM.
#11
zvh maybe??
http://www.ebay.co.uk/itm/GENUINE-FO...item5ad9a83b0c
i`m tempted.
you going national day mate?
http://www.ebay.co.uk/itm/GENUINE-FO...item5ad9a83b0c
i`m tempted.
you going national day mate?
#12
12,000 miles, im surprised it failed after 12k!
When you rebuild, strip the oil pump down to and give it a good clean, then use carb cleaner and a compressor to clean out the oil galleries, you can never be too clean. What do your other bearings look like?
TBH you could make a budget ZT for about the cost of your rebuild, run low(ish) boost until you have the money to do it properly, plus you would break even after selling the tasty bits off yours, imo 250bhp on a standard zetec is possible.
Standard bottom end, redrilled head to accept rst manifold maybe a decomp plate and your away. 3-400 should happily do that and get you out of a hole.
I must have been blind not to have seen your car have to swap mobile numbers before the next show.
Rob,
When you rebuild, strip the oil pump down to and give it a good clean, then use carb cleaner and a compressor to clean out the oil galleries, you can never be too clean. What do your other bearings look like?
TBH you could make a budget ZT for about the cost of your rebuild, run low(ish) boost until you have the money to do it properly, plus you would break even after selling the tasty bits off yours, imo 250bhp on a standard zetec is possible.
Standard bottom end, redrilled head to accept rst manifold maybe a decomp plate and your away. 3-400 should happily do that and get you out of a hole.
I must have been blind not to have seen your car have to swap mobile numbers before the next show.
Rob,
#13
Have a look at this Karlos, providing its gen you wouldn't need to rebuild the bottom end, it will take low boost and a little more with a pikey decomp plate.
330600530938 (ebay num)
Rob,
330600530938 (ebay num)
Rob,
#14
You know what Rob I think that is the way to go!
As you say a decomp plate and use my manifolds = 250bhp job done!
My NMS head is worth Ł500, SS valves, bronze guides etc. with the Newman cam/lifters and vernier!
Wossner pistons and PEC rods Ł350!
60k EFI block with good stock bores Ł100?
That will cover the cost of the ZT bits easy!
As you say a decomp plate and use my manifolds = 250bhp job done!
My NMS head is worth Ł500, SS valves, bronze guides etc. with the Newman cam/lifters and vernier!
Wossner pistons and PEC rods Ł350!
60k EFI block with good stock bores Ł100?
That will cover the cost of the ZT bits easy!
#15
You know what Rob I think that is the way to go!
As you say a decomp plate and use my manifolds = 250bhp job done!
My NMS head is worth Ł500, SS valves, bronze guides etc. with the Newman cam/lifters and vernier!
Wossner pistons and PEC rods Ł350!
60k EFI block with good stock bores Ł100?
That will cover the cost of the ZT bits easy!
As you say a decomp plate and use my manifolds = 250bhp job done!
My NMS head is worth Ł500, SS valves, bronze guides etc. with the Newman cam/lifters and vernier!
Wossner pistons and PEC rods Ł350!
60k EFI block with good stock bores Ł100?
That will cover the cost of the ZT bits easy!
#16
Sounds like a good idea Gary but those ST170 engines are not going to be cheap surely?
Are the ST170 pistons and rods stronger than the blacktop then?
Are the ST170 pistons and rods stronger than the blacktop then?
Last edited by Karlos G; 12-08-2011 at 05:35 PM.
#18
yes mate they are . zetec rods are fine at over 300hp with just a set of arp rod bolts but the pistons are crap, you could use let pistons with the zetec bottom end and still be good for over 300hp
#20
#21
It's a CP2000-35 I think they are used at 300bhp+ on a CVH which would probably be similair torque.... I can just run a little less for now! lol
Will it fit the Duratec fly wheel though?
Cheers for your help BTW Gary!
Will it fit the Duratec fly wheel though?
Cheers for your help BTW Gary!
#22
what will standard zetec pistons handle, just out of interest? would be happy with a solid 250bhp on mine eventually, lining up either zvh or full zt and mtx when 1.6 goes pop. also will the 220mm ap paddle clutch handle it?
#23
You know what Rob I think that is the way to go!
As you say a decomp plate and use my manifolds = 250bhp job done!
My NMS head is worth Ł500, SS valves, bronze guides etc. with the Newman cam/lifters and vernier!
Wossner pistons and PEC rods Ł350!
60k EFI block with good stock bores Ł100?
That will cover the cost of the ZT bits easy!
As you say a decomp plate and use my manifolds = 250bhp job done!
My NMS head is worth Ł500, SS valves, bronze guides etc. with the Newman cam/lifters and vernier!
Wossner pistons and PEC rods Ł350!
60k EFI block with good stock bores Ł100?
That will cover the cost of the ZT bits easy!
Good stuff mate, you can always save up for a decent ZT spec and have a nice fun reliable engine for the mean time.
PS, there are a few adapter plates around that let you bolt your manifolds right on the zetec head, means you can keep your new 3i inlet too.
Or as Gary says some LET pistons which are fairly cheap. That new zetec engine on the bay seems a steel at that money and it means you wouldn't need to replace bottom end bearings to be safe + it will have been built to factory tolerances.
Like Gary says if you find an ST170 thats got to be worth it.
Happy hunting
Rob,
#24
Sorry to hijack Karlos; What CR does that give Gary? If I sell all my L8 stuff and my engine i'll be able to afford that!
#25
Good stuff mate, you can always save up for a decent ZT spec and have a nice fun reliable engine for the mean time.
PS, there are a few adapter plates around that let you bolt your manifolds right on the zetec head, means you can keep your new 3i inlet too.
Or as Gary says some LET pistons which are fairly cheap. That new zetec engine on the bay seems a steel at that money and it means you wouldn't need to replace bottom end bearings to be safe + it will have been built to factory tolerances.
Like Gary says if you find an ST170 thats got to be worth it.
Happy hunting
Rob,
PS, there are a few adapter plates around that let you bolt your manifolds right on the zetec head, means you can keep your new 3i inlet too.
Or as Gary says some LET pistons which are fairly cheap. That new zetec engine on the bay seems a steel at that money and it means you wouldn't need to replace bottom end bearings to be safe + it will have been built to factory tolerances.
Like Gary says if you find an ST170 thats got to be worth it.
Happy hunting
Rob,
No worries mate I was going to ask the same question!
#28
I just noticed the ford stamp on the bearing.. Maybe use some better ones next time.
clevite is the best choice in this situation as mahle dont make the race bearings for the cvh.
clevite is the best choice in this situation as mahle dont make the race bearings for the cvh.
#29
#31
Karlos did you stretch the ARP conrod bolts correctly when building the engine up, you could measure the length of the bolts, but without knowing what length they were on final build, comparing them to another new bolt that hasnt stretched yet wouldnt really give you a good enough comparison.
#32
I lubed them up and torqued them up, they are a use once item, what do you mean by stretch them correctly once stretched they are no use? Unless they happen to still be within tolerance, which is unlikely.
#33
I thought the st170 pistons were forged, why use let pistons instead of these?
#35
Interesting, I'll pm you my email address as I dont have yours...
Last edited by Karlos G; 13-08-2011 at 09:55 AM.
#36
You'll need to resize the conrod, depending by how much you may need to do all 4. Probably just the one by the looks of it. Difficult to pinpoint why it happened. The crank will likely be oval so need a regrind.
Rick
Rick
#39
#40
Its a very american thing to do, i didn't really do it with my engine, instead i torqued the bolts up and measured them to check they were all a consistent, the amount of stretch is also very dependant upon which oil you used.
Its more often done with a rod that has a nut and bolt. You torque the nut and not the bolt meaning more force is used to stretch the bolt and less lost to friction. I very much its why your bearing failed. It failed due to the reasons in my first post i can guarantee it.
PS this is the normal type of rod bolt set up stretch tightening is usually used on.
Rob,