Another BEB thread……

[SKULLGRINDER]

Not new to cruisers but this is my first 1HD-T. ( 1990 HDJ81 ). With that said PO claimed to have BEB done 80k ago and while I do have supporting paperwork from ATEB years ago I’ve obviously read it’s the only major issues that plagued these motors. Where I could use some clarification is once the rod bearings themselves were updated, is it a do once and you’re done or is it something you continue to do as a PM every 100k? I’ve heard both ways on it. For reference my motor is a bone stock 1HD-T with a g turbo. Pump hasn’t been opened up. 3” stainless back

Appreciate the information and help dudes!

 

[rick_d]

Hayden
I would just replace the big end bearings and rod bolts (and timing belt) just to zero everything out. Cheap insurance.

 

[duece71]

Black stone Labs for oil analysis will show if there is anything potentially fatal going on.

 

[Hulsty]

1HDT the BEB are a regular replacement item like the timing belt, swap them out

 

[mudgudgeon]

Black stone Labs for oil analysis will show if there is anything potentially fatal going on.

1HDT the BEB are a regular replacement item like the timing belt, swap them out

Two sides of one coin right there ^^^^


Choose one of these approaches, depending on your appetite for risk VS spending money on preventative maintenance that may or may not be needed.

There's tens of thousands of 1hd-t that will live out there life on original BEBs, and there's some that will be in bad shape after 100k km.

Oil testing can help you make an informed decision.

Personally, i think there's some risk in opening the engine and changing BEBs prematurely. On the flip side, a total failure of a BEB can result in a catastrophic engine failure.

You decide what you're comfortable with.

 

[SKULLGRINDER]

Two sides of one coin right there ^^^^


Choose one of these approaches, depending on your appetite for risk VS spending money on preventative maintenance that may or may not be needed.

There's tens of thousands of 1hd-t that will live out there life on original BEBs, and there's some that will be in bad shape after 100k km.

Oil testing can help you make an informed decision.

Personally, i think there's some risk in opening the engine and changing BEBs prematurely. On the flip side, a total failure of a BEB can result in a catastrophic engine failure.

You decide what you're comfortable with.

I hear ya. Much like the 1FZ with its Hg "issue". Some guys replacing them at 180k and others who have had them fail prematurely and tarnish the name of the 1Z because they had a poor experience. Then there is the other side of the court which I am personally in with the 1FZ where I am going 340k strong on the original HG. In my opinion with these older cruisers you have to have some respect for what it is and realize its limitation and when it's not happy to ease off and let it do its thing before it hurts itself. With all that being said my plan of attack here is to send a sample of oil to Blackstone just for my curiosity but also get the appropriate parts to do a proper BEB and timing belt job along with some other miscellaneous items (with fear of overseas items getting harder to get over the line) for my own piece of mind to keep this thing on the road for years to come because lets be honest...... out of my 3 this is hands down my most favorite!

 

[Dougal]

It's a cavitation problem in the crank, so they need regular replacement. Oil analysis will show anything loose, but it won't show a chunk of bearing material that's fatigued and about to let go.

Change them every 100,000km.

 

[rick_d]

^^^^^
THIS

 

[GreenPump]

Agree with @Dougal .

My 1993 was on its second set of BeBs at 410km. When changed, they had just started to delaminate on Cyl 6. Caught before anything serious started.

If you use some plastigauge to measure the bearing clearance on the new ones you put in, the risk of out-of-spec clearances can be eliminated. On the off chance somehow your conrod bearings are not STD, you will only discover that with plastigauge. Doubt you could tell by looking. Upside-down plastigauge under the truck is no fun, but it works

I've had a conrod bolt or two snap after the third time re-torqueing them. So I usually replace them too. Have had good luck with ACL parts.

 

[duece71]

Agree with @Dougal .

My 1993 was on its second set of BeBs at 410km. When changed, they had just started to delaminate on Cyl 6. Caught before anything serious started.

If you use some plastigauge to measure the bearing clearance on the new ones you put in, the risk of out-of-spec clearances can be eliminated. On the off chance somehow your conrod bearings are not STD, you will only discover that with plastigauge. Doubt you could tell by looking. Upside-down plastigauge under the truck is no fun, but it works

I've had a conrod bolt or two snap after the third time re-torqueing them. So I usually replace them too. Have had good luck with ACL parts.

If someone doesn’t know exactly which BEBs are in there (PO had them done at 154313 miles or 248,000 KMs) would it be best to tear it down, see which BEBs are in there and then order or just order? PO also replaced the rod bolts with brand new. Truck is now just shy of 275,000 KMs so I think I have a ways to go before getting ready to do them. What about some sort of coating on the BEBs before installing?

 

[Dougal]

Reposting this from the other thread: 1HDT BEBs Unique Problem - https://forum.ih8mud.com/threads/1hdt-bebs-unique-problem.1366720/

Yes it's a cavitation/resonance problem that causes the damage and it's probably at that rpm. I think the reason Australia found this problem early and NZ didn't was because Australians spend a long time at constant speed where Kiwi's don't.

Here's a relevant research paper: https://www.tytlabs.co.jp/en/english/review/rev401epdf/e401_036aoyama.pdf Analysis of crankshaft cavitation on a 6 cylinder diesel engine. One of the authors is a Toyota Engineer. Hmmm........

They have a modification to prevent it. But I don't know of anyone else who's tried it.

 

[SKULLGRINDER]

Finally got around to doing my BEB after taking care of some stuff on the top end of the motor. Lone behold no delamination and pretty minimal wear accept for cyl 3.