Spigot bearing

[Bobbybedtime]

Hi all.
Upgrading my TVR 350i with a 3.9 engine. In the process I've aquired an extra two cranks. One from the short block I purchased and one I got spare with some pistons I bought.
The short block crank is worn, the spare one with pistons is spot on. Went to put in a new spigot bearing before getting it all balanced and it turns out I may have an odd crank. Where the spigot bearing fits into the crankshaft ... the hole is to big. The new bearing I have is from RPI and is for 3.5/3.9 with manual gearbox. Its the same as the original spigot bearing in the 3.5 motor and the same as the one out of the short block. It seems the good spare is an odd size. The o.d. of the new bearing is 23.9mm. The o.d. of the one that came out is 26.9mm. Spoke with real steel and they advised all rover v8 cranks had the same I.D. where the spigot bearing goes . If I can post a picture I will ... any ideas why I my crank seems odd?

Thanks,
BBT.

[TVRleigh_BBWR]

AFAIK they all should be the same size even the later LR 4.0 and 4.6 Thor engines, as that what I have in the racer and use a LT77 box.

[Bobbybedtime]

Thats what the fella from real seel said. I'm wondering if I have a buick crank or may its been turned out for a reason. Guess Im concerned now some of the othe dimensions may be different ... like the stroke .. gulp.

[rev-erend]

Maybe someone gave you the wrong one..

[Bobbybedtime]

Possibly, it did have all eight pistons and rods connected. All identical to those in the short block. Only wanted two pistons originally but it was all better than mine.
I did put crank in block to check end float and it was spot on.

[Bobbybedtime]

http://thumbsnap.com/a46V9R5Y

[TVRleigh_BBWR]

Bobbybedtime said:

http://thumbsnap.com/a46V9R5Y

Yes does look a bit large.
you could just make a sleeve 1 thou over size so you can press it in, to reduce the size to take the standard bearing.

[rev-erend]

That does not look right.

I have both engines serp and older and both types took the same size spigot bearing and is the thicker looking of the two you have there.

Could it be that the auto box has a different crank/spigot bearing ?

[plushuit]

Bobbybedtime said:

Hi all.
any ideas why I my crank seems odd? Thanks, BBT.

Sure.

Rpi sent you the right spigot bearing (aka spigot bush). You simply have the wrong crank for it. The spigot bearing you have will fit your car's original crank. It is used with all 2 wheel drives using the R380 or the LT77.

But the cranks you have are for LR 4x4s. I imagine any machine shop can make you up a special spigot bearing that will do the trick..that part is not the problem. Simply confirm have much of an interference fit you need and take them the spigot bearing you have from Rpi for them to determine the right ID. What I don't know is the effect (if any) of using a 4x4 truck crank in a sports car. Why don't you weigh it and compare with the old crank?

BTW, there is an easy way of getting a spigot bearing out without damaging it or anything else. Fill the spigot bearing hole with grease and use a tight fitting rod...or the clutch alignment tool and rubber hammer it in. The spigot bearing will pop out politely, forced out by the grease.

L.

[rev-erend]

Truck crank .. like that.

[TVRleigh_BBWR]

plushuit said:

Sure.

Rpi sent you the right spigot bearing (aka spigot bush). You simply have the wrong crank for it. The spigot bearing you have will fit your car's original crank. It is used with all 2 wheel drives using the R380 or the LT77.

But the cranks you have are for LR 4x4s. I imagine any machine shop can make you up a special spigot bearing that will do the trick..that part is not the problem. Simply confirm have much of an interference fit you need and take them the spigot bearing you have from Rpi for them to determine the right ID. What I don't know is the effect (if any) of using a 4x4 truck crank in a sports car. Why don't you weigh it and compare with the old crank?

BTW, there is an easy way of getting a spigot bearing out without damaging it or anything else. Fill the spigot bearing hole with grease and use a tight fitting rod...or the clutch alignment tool and rubber hammer it in. The spigot bearing will pop out politely, forced out by the grease.

L.

The cranks in your picture have the same ID for the bush, it's just the 4x4 and 2wd bushes have different id, but they should have the same OD

I've got a 3.9 LR 4x4 crank in my race engine, and it's been fine.

Good tip on the removal, I had read about that method before. but not till after I made a right mess getting the 4x4 one out of my crank.

[Bobbybedtime]

Thanks gents.
Agree nothing wrong with what RPI sent, it would fit two of the three cranks I have, just turns out the best one has a larger hole for the spigot bush. I'll check the material and get something made to fit. Appreciate the info given.
BTW both cranks weigh 39.6 lbs.
I've attached another photo, one crank is slightly closer but the difference can be seen.
http://thumbsnap.com/JmjqufE1
Regards,
Bob.

[rev-erend]

Mut be a sturdy table

[Bobbybedtime]

Just got an email from the seller below. Advises me the bush has 27mm diameter. Same as mine. Just need one with an ID of about 12.6mm (not 22.3mm) for my gearbox. Its for a Land Rover Defender 300 spigot bearing bush LFB500050

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&am...

Rgds,
Bob.

[Bobbybedtime]

My post above is rubbish as it looks like its from a diesel .....

[Wedg1e]

I seem to recall from my rebuild (a decade ago, so I may be wrong!) that the automatic gearbox used a different spigot bush.

[TVRleigh_BBWR]

Wedg1e said:

I seem to recall from my rebuild (a decade ago, so I may be wrong!) that the automatic gearbox used a different spigot bush.

Yes there are 2 sizes, (well 3 if you inc the one for the T5 Box) but all have the same external dimensions, and hence the hole in all the cranks should be the same size, but it looks like the one he has, has been drill/bored to a larger size.
as said before the easiest way to get get a machine shop to make a sleeve to reduce the size.

[Wedg1e]

TVRleigh_BBWR said:

Yes there are 2 sizes, (well 3 if you inc the one for the T5 Box) but all have the same external dimensions, and hence the hole in all the cranks should be the same size, but it looks like the one he has, has been drill/bored to a larger size.
as said before the easiest way to get get a machine shop to make a sleeve to reduce the size.

Ah yes, read the thread in a hurry

Bit of bronze, vernier, lathe, job done.