Printable Version | Subscribe | Add to Favourites
New Topic New Poll New Reply
Author: Subject: Big End Bearing run in
RobBrown

posted on 28/8/16 at 05:54 PM Reply With Quote
Big End Bearing run in

Hi
On a previous post I described some engine knocking once the engine had warmed up.

YouTube Link

After a bit of research I concluded that one or more of the Conrod Bearings had gone.

I removed the following bearings on two of the cylinders
Knocking Conrod bearing
Knocking Conrod bearing


I can tell the difference in weight between the two sets and it looks like the bottom set have been spinning around the crank.
The sump also has the rest o the bearing shells in
Sump shiny bits of bearing
Sump shiny bits of bearing


So my question is when I replace them is there a running in procedure as the is with a camshaft, in order to bed them in a little?

Also is there anything else I should do whilst I have the sump off

Thanks
Rob

View User's Profile View All Posts By User U2U Member
rusty nuts

posted on 28/8/16 at 06:11 PM Reply With Quote
At the very least you need to get the crank measured and probably reground, clean out all debris in engine and perhaps replace the oil pump. Would be a good idea to check the cam and followers as well. (Well known Pinto weak spot)
View User's Profile View All Posts By User U2U Member
perksy

posted on 28/8/16 at 06:47 PM Reply With Quote
Two of those have picked-up and overheated badly, the others are scored badly

As said the crank needs checking for scoring and ovality and I'd be surprised if there isn't 'crud' in the rest of the engine

Big end bearings don't need running in as such but what they do need is correctly sizing and fitting correctly
You also need to give them the best possible chance and if the crank is damaged/worn they won't last long
(I always use rebuilding fluid and plastigauge them on trial fitting)


I'd heard your youtube video and was just about to say it was big ends


I'd also be checking the other bearings, but something has gone wrong on those two cylinders and it needs sorting
They look like they've run shy of oil

As said above check the camshaft and pay particular attention to the oil spray bar, they are famous for blocking up on pinto's


Just finished rebuilding a pinto for a mate and that's ended up with a crank, new mains and big ends and camshaft (+ oil spraybar) and the big end bearings didn't look as bad as those

[Edited on 28/8/16 by perksy]

View User's Profile View All Posts By User U2U Member
RobBrown

posted on 28/8/16 at 06:49 PM Reply With Quote
Any idea on how much that should cost? Are we talking £50-£100 or £250+

Presumably will need new main bearings and thrustwashers too?

Rob

View User's Profile View All Posts By User U2U Member
perksy

posted on 28/8/16 at 07:00 PM Reply With Quote
To be fair it depends on how much you can do yourself and what tools/facilities you have ?

It ain't easy doing this under the car with the sump off but i'd remove all the big end caps first and see what state the crank journals are in ?
If the journals are scored then the engine is coming out i'm afraid

View User's Profile View All Posts By User U2U Member
RobBrown

posted on 28/8/16 at 07:18 PM Reply With Quote
quote:
Originally posted by perksy
To be fair it depends on how much you can do yourself and what tools/facilities you have ?

It ain't easy doing this under the car with the sump off but i'd remove all the big end caps first and see what state the crank journals are in ?
If the journals are scored then the engine is coming out i'm afraid


The other two cylinders are off and the bearings are in the same state as the best one in the first pic were off (top set). The one cylinder appears to have been the main culprit for the knocking but seeing as the others are in a similar state I need to find out why the 4th went so bad

I have most tools and the space and the inclination. What I don't have is the engineering tools for crank measurement and regrinding. I also don't have any local contacts for this sort of work and have an office job, so have to do things in the evenings and weekends which doesn't help.

I'm probably more wary of costs. I can get a reconditioned block for £850; so don't want to spend £100 here, £100 there etc to find that by the end of it I've spend weeks of time and money on something that could have been fixed by getting in a reconditioned replacement for less.

I have a new cam and followers and a new spray bar on top so reasonably confident in the top end.

Rob

[Edited on 28/8/16 by RobBrown]

View User's Profile View All Posts By User U2U Member
RobBrown

posted on 28/8/16 at 07:42 PM Reply With Quote
Looks like as a minimum the worse affected journal needs a repolish. I can feel the roughness, but isn't scored.

Description
Description




There's a place in Oxfordshire, just over an hour away which quote £3 per journal for repolishing or £12 per Journal for regrinding.

Will give them a call on Tuesday (Bank Holiday tomorrow )RobWalkerEngineering

Rob

View User's Profile View All Posts By User U2U Member
britishtrident

posted on 28/8/16 at 07:45 PM Reply With Quote
Post an ad to see if anybody has a spare Pinto, somebody will have one lying around.





[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]

View User's Profile View All Posts By User U2U Member
ashg

posted on 29/8/16 at 12:01 AM Reply With Quote
Get some 2000 grit wet and dry from halfords cut a long piece of it to the width of the journal put oil all over it then put it round the journal and move it back and forwards going round evenly. if it's just shel material stuck to the crank it should come off and clean up to a nice finish again. Once your done hose the journal off with wd40 with a straw up the oil way to wash any crap. Reassemble wig new shells and measure clearance with a plasti gauge if it's ok run it and see how it goes. It's always worth a shot for the cost of a set of shells as it's much cheaper than a new motor.

I have done it this way on several engines and they have all been fine for thousands of miles other than one, it takes some serious abuse to get a crank journal to go oval.





Anything With Tits or Wheels Will cost you MONEY!!

Haynes Roadster (Finished)
Exocet (Finished & Sold)
New Project (Started)

View User's Profile View All Posts By User U2U Member
scimjim

posted on 29/8/16 at 07:14 AM Reply With Quote
South Cerney Engineering have a good reputation and may be a bit closer?
View User's Profile View All Posts By User U2U Member
mkindypaul

posted on 29/8/16 at 08:37 AM Reply With Quote
With it knocking like that on tickover I'd say a crank regrind is the way I'd go and also check the oil pump etc for the reason it's done it, you say in your post the bearing had spun on the crank ? If so you'll need the rod and cap measured.
View User's Profile View All Posts By User U2U Member
mcerd1

posted on 29/8/16 at 08:54 AM Reply With Quote
quote:
Originally posted by RobBrown
I'm probably more wary of costs. I can get a reconditioned block for £850; so don't want to spend £100 here, £100 there etc to find that by the end of it I've spend weeks of time and money on something that could have been fixed by getting in a reconditioned replacement for less.

a good second hand short block will be the cheapest option if you can find one that you trust....

£850 seems a fit steep for a bog standard recon pinto too me, but I guess it depends whats been done to it

quote:
Originally posted by RobBrown
I have a new cam and followers and a new spray bar on top so reasonably confident in the top end.

I'd strip and clean everything then change the spray bar as a minimum (they are only £10) - one metal particle in the wrong place could kill your cam

http://www.burtonpower.com/camshaft-oil-spray-bar-ford-sohc-pinto-ft1059.html





-

View User's Profile View All Posts By User U2U Member
britishtrident

posted on 29/8/16 at 12:24 PM Reply With Quote
To have one big end go is the norm but two failing indicates something more is wrong.





[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]

View User's Profile View All Posts By User U2U Member
RobBrown

posted on 29/8/16 at 12:36 PM Reply With Quote
quote:
Originally posted by mkindypaul
With it knocking like that on tickover I'd say a crank regrind is the way I'd go and also check the oil pump etc for the reason it's done it, you say in your post the bearing had spun on the crank ? If so you'll need the rod and cap measured.


The rod and cap have the same black burnt look about them so definitely needs checking.

Can you get away with a single new rod or do you have to buy a complete set of 4?

Rob

View User's Profile View All Posts By User U2U Member
mkindypaul

posted on 29/8/16 at 12:46 PM Reply With Quote
As long as the others havnt spun then the rest will be fine, need to try and find out why it's done it as well. What sump do you run it could of been oil starvation ?
View User's Profile View All Posts By User U2U Member
rusty nuts

posted on 29/8/16 at 12:52 PM Reply With Quote
It's almost a certainty that it has suffered due to lack of oil possibly due to the oil in the pump draining back whilst standing ? Priming the pump before starting may have saved this problem ? Easy to say in hindsight
View User's Profile View All Posts By User U2U Member
RobBrown

posted on 29/8/16 at 12:58 PM Reply With Quote
quote:
Originally posted by mkindypaul
As long as the others havnt spun then the rest will be fine, need to try and find out why it's done it as well. What sump do you run it could of been oil starvation ?


Standard Sump. It could have been run low of oil at some point - but I'll get the oil pump out. My pressure sender shows a consistent 5-6 bar of pressure when running - so could just be the low oil.

In the process of getting it all out. Just on a lunch break

I'll clean everything down.

Get the Crank checked, ground and balanced, ifrequired
New Conrod to replace the burnt out one.
New Conrod bearing (size depending on regrind)
New Main bearings (size depending on regrind) and thrustwashers
New spray bar
May splash out on a new oil pump, as that's bound to be the next thing when it's all back together.

Rob

View User's Profile View All Posts By User U2U Member
mkindypaul

posted on 29/8/16 at 01:01 PM Reply With Quote
Yeah go high pressure for the pump whilst it's out, use a good quality oil to like valvoline vr1.

[Edited on 29/8/16 by mkindypaul]

View User's Profile View All Posts By User U2U Member

New Topic New Poll New Reply


go to top






Website design and SEO by Studio Montage

All content © 2001-16 LocostBuilders. Reproduction prohibited
Opinions expressed in public posts are those of the author and do not necessarily represent
the views of other users or any member of the LocostBuilders team.
Running XMB 1.8 Partagium [© 2002 XMB Group] on Apache under CentOS Linux
Founded, built and operated by ChrisW.