Big End Bearings

[jun85]

Dear All,
I fear the time has come to get my BEB changed as some good preventative maintenance.
I will not be undertaking this task myself but will get my local garage to do it.
Please can someone advise what parts need ordering and what the to do list should be resulting in a proper job?
I have a 1994 turbo diesel 12 valve.

Thanks

John

 

[Rifleman]

Just a request, but would it be possible for you to convert what Big End Bearings are, and where they are located on the Engine, or chassis/drive train for those of us that live across the pond in the colonies?

 

[Pin_Head]

They are the crankshaft rod bearings and they are not something that one would do as preventative maintenance. If you have experienced some kind of catastrophic lubrication failure, then maybe you would need to replace them. Engine oil analysis might help you decide.

 

[RockDoc]

@jun85
If you wander over to the diesel and 24 volt section on mud here, you'll find more existing information and a higher concentration of members who know what you're talking about than you will here in the 80 series section.

 

[jun85]

@jun85
If you wander over to the diesel and 24 volt section on mud here, you'll find more existing information and a higher concentration of members who know what you're talking about than you will here in the 80 series section.

Oh ok. Sorry for the misplaced question. Thanks.

 

[maxamillion2345]

They are the crankshaft rod bearings and they are not something that one would do as preventative maintenance. If you have experienced some kind of catastrophic lubrication failure, then maybe you would need to replace them. Engine oil analysis might help you decide.

1HD*s have a known BEB delam problem. Its common place to replace them before failure.

 

[maxamillion2345]

Oh ok. Sorry for the misplaced question. Thanks.

Not misplaced but you’ll find better answers in the diesel tech/24v forum.

 

[maxamillion2345]

Just a request, but would it be possible for you to convert what Big End Bearings are, and where they are located on the Engine, or chassis/drive train for those of us that live across the pond in the colonies?

Big end of the con rod as opposed to wrist pin

 

[thatcabledude]

All this time I thought it was "bottom end bearings"

 

[Pin_Head]

It could be hysteria too, like head gasket replacement on 1FZFEs.
I read all the threads in the diesel section and I saw a lot of normal looking bearings a few pitted bearings in the normal range and no reports of spun bearings / crank journal failure. Google did not turn up any Toyota service bulletin on this issue either.

 

[ppc]

The BEB problem has been a well documented issue for ~20+ years with the 80 Series Land Cruiser diesel motors. Don't know which variations/engine models but there was documentation including pictures of failed motors on the 80Scool forum.

 

[Pin_Head]

The BEB problem has been a well documented issue

As is the head gasket issue for the 1FZ-FE. That dosn’t mean that it makes good sense to replace it as “preventative maintenance”. For both issues, most people never have problems and people that “preventatively” replace have problems anyway. If it ain’t broke, don’t fix it.

 

[ppc]

The difference is with a head gasket failure you can with minimal machining and parts replace the head gasket at relatively small cost. With BEB failure your chances of having to do a complete engine rebuild is very high at much greater cost. The preventive, proactive costs are much much less than a potential rebuild and far less labor than a head gasket replacement.

 

[Pin_Head]

So what? Most people won’t realize a benefit on either preventative maintenance items because they won’t fail.

A head gasket job is $2K and a new engine is an extra 4K. It doesn’t make sense to just change a head gasket on a high mileage engine.

For most people the engine wears out before any bearing failure and for most bearing failures, the engine needs to be rebuilt anyway. Why put $1000 into changing the rod bearings on a high mileage engine when it is going to need $5000 more 50K miles later. “If it ain’t broke, don’t fix it.”

 

[ppc]

"For most people the engine wears out before any bearing failure and for most bearing failures, the engine needs to be rebuilt anyway. Why put $1000 into changing the rod bearings on a high mileage engine when it is going to need $5000 more 50K miles later. “If it ain’t broke, don’t fix it.” "

I would agree with you more so if you are only considering the 1FZ-FE. The only 1FZ-FE that I recall having issues with BEBs is where the head gasket failed and the motor sat with coolant in the oil pan for an extended period of time. Not so with the diesel, there have been instances where replacing the BEBs as preventive maintence has saved the motor before damage to the crank that would require polishing if not replacement of the crank. Replacement of the BEBs is much simplier and far less costly than a head gasket. @jun85 should be able to supply a quote of the costs.

 

[jun85]

Ok so I think the main issue here is that there are many more 80s diesels over here as the petrol isn’t quite as popular. Mostly due to our fuel costs.
Regarding the big end bearings - it seems a very popular preventative for the diesel. In fact, most people over regard it as an absolutely critical part of maintainance on these old engines.
I’ve put a tonne of time and cash into making my 80 mechanically sound for the future.
Someone’s said it’s like a 3/4 hour job. I’m just not sure what best parts are and what else they should do whilst ‘in there’.

 

[B Point]

Just get them done or do them yourself. It's a dirty job but it's an easy job.....worse than a knuckle overhaul in that sense. At 160k miles or so mine needed changing. I'm coming up on another 100k and I'm getting psyched up to do them again within the next year or two. It's a PM job but it's definitely more than a 3/4 hour job.

 

[Jroc561]

It could be hysteria too, like head gasket replacement on 1FZFEs.
I read all the threads in the diesel section and I saw a lot of normal looking bearings a few pitted bearings in the normal range and no reports of spun bearings / crank journal failure. Google did not turn up any Toyota service bulletin on this issue either.

I somewhat agree with this, every internet forum drives some hysteria. Headbolts in a 63amg, rod bearings in a s54, transmissions in the 350z. But atleast replacing the BEBs is pretty cheap, couple hundred in parts and can be done in just a few hours.

 

[Douglas S]

So what? Most people won’t realize a benefit on either preventative maintenance items because they won’t fail.

A head gasket job is $2K and a new engine is an extra 4K. It doesn’t make sense to just change a head gasket on a high mileage engine.

For most people the engine wears out before any bearing failure and for most bearing failures, the engine needs to be rebuilt anyway. Why put $1000 into changing the rod bearings on a high mileage engine when it is going to need $5000 more 50K miles later. “If it ain’t broke, don’t fix it.”

A 1HD-T isn't a cheap engine. BEB fails and you destroy one and you're looking at 7 or 8 grand plus freight just to get a used motor to replace it.

BEB's with new bolts are a couple hundred and then a few hours of time to pull the pan and replace them. There are some members of this very forum that had the same attitude as you; some of them now have rebuilt motors and some of them ended up parting out their trucks (I think that says a lot given that the % of people on this forum who have done the BEB replacement is lilely much higher than the general ownership). The issue is widespread, well documented, and a lot easier to deal with than a head gasket. The results of rolling the dice and losing are also a lot more severe.

Normally I think the PM crowd on this forum are a bit ridiculous, but this is one thing I wouldn't chance.

 

[Douglas S]

double