Extension Crank Bolt Attachment

[Redoakboo]

I am finishing up the reassembly of my rebuilt TR-2 engine. I have just installed the crank collar/pulley & fan. I am now installing the long bolt that the crank handle fits into. I can't find the torque setting for this bolt, not in the TR manual; I can't find it?

Dick

[TR3driver]

I don't believe there is one in the manuals. It's not critical; anything in the 120-150 ftlb range should do fine.

[Geo Hahn]

If you plan to use the hand-crank to start the car (requires you retain the hole in the radiator) then there is a recommended orientation for that dog on the front of the bolt. Without looking I am thinking it is 4:00 / 10:00 for the flats of the 'teeth' when at #1 TDC.

To get that and about the right torque shims may be used.

[Redoakboo]

Randall.

When it gets up to about 40# it seems to start slipping? I took the collar off to make sure the woodruff key had not come out of the slot, it hadn't? Should the collar be touching the crank sprocket? I have about a 1/4" gap between the collar and the sprocket. Tried to force further with a hammer, no dice? All the threads look good.

Dick

[TR3driver]

Yes, the dog bolt should clamp the whole mess together solidly: fan extension, pulley hub, oil slinger, timing chain sprocket, and any shims behind the sprocket should all get clamped tightly against the front cheek of the crankshaft. And a snug fit on the crankshaft is good. Sounds like you are OK.

[Redoakboo]

But, why can I not torque the dog bolt any tighter then about40#? When I have the whole assembly, fan extension, pulley hub, oil slinger, timing chain sprocket, and a couple of shims as tight as I can get them on with a hammer, I still have about 1/4" gap between the pulley hub and the sprocket, not a particular snug fit? When the torque wrench only reaches about 40#, tightening the dog bolt, before it starts to slip. To keep the crank from turning, while I'm tightening the bolt, I have a square bar between the rear bolts of the rear crank hub.,flywheel not installed yet.

I just don't want to take a risk of slinging that bolt out when I finally get the engine running again.

Thanks for your help, Randall

Dick

Dick

[TR3driver]

I think your "slip" is the pulley hub continuing to move towards the sprocket, as it should. The hub is evidently tight enough on the shaft that your hammering (not a particularly good idea, BTW) did not move it into place.

Try letting it "slip" for a turn or two, and check again. I think you'll find that the hub moved towards the crankshaft (by about 1/9" for two turns). Of course, if you're doing this without the timing cover (so you can see that gap), then you'll probably have to use a puller to get it back off again. Might be best to put the timing cover on first.

I doubt it would "sling the bolt out"; but every time the engine fires, it puts a torque pulse into all those parts. If they can move at all, they will work back and forth (even with the key in place) and eventually get ruined. I made a mistake once when eliminating the fan extension (to make room for the electric fan), and it eventually waddled the keyway out to about 1/2" wide! Both keys were in bad shape, but still in place.

Made the funniest noise, too. At idle, sounded like someone was ringing a bell inside the engine.

[Redoakboo]

I just thought of something, in my dream last night! You know that dreams are great at reminding you what you forgot to do? I have installed one of the new yellow fans, backwards, so I won't have to buy an expensive new spindle, so says Albert at Roadster Fact. I think if I remove the fan and then try to tighten the bolt it might just work. It appears the fans goes over the bolt anyway, encase you ever had to replace the fan, you would not have to remove the "subject" bolt?.

The timing cover is on, but I still have a good view of the gap between the collar and the sprocket.

Will try your suggestion today, thanks again for your help; wished you lived in Clermont Fl. !

Dick

[TR3driver]

Right, tighten the bolt before installing the fan. The stock fan mount even includes a keeper that fits over the hex and keeps the bolt from turning.

I don't understand your comment about being able to see the gap ... The sprocket isn't even visible through the hole before adding the hub. The oil slinger goes between the cover and sprocket, and is larger than the hole, so all you could see is the oil slinger. And IIRC the hub goes into the seal by more than 1/4". So if it is within 1/4", it would already be touching the seal.

But I don't suppose it matters, as long as you understand.

[Redoakboo]

Thanks agin!! Randall.

I removed the fan, installed a new shim, they sure get trashed when you tighten the bolt. Was now able to tighten to 120#, that's as high as my torque wrench will go. You are right as the gap I was addressing was between the edge of the collar right at the timing cover.

Why does R.F. recommend installing the yellow fan backwards, unless you buy one of the special spindles. I assume it would put it to close to the radiator?

Dick

[TR3driver]

I believe that is the issue, the fan sticks out too far. But I have no experience with that mod; prefer my electric fan setup

[Redoakboo]

I have an electric fan on my TR-3, and a holeless aluminum radiator, keeps it cool.

I couldn't salvage the TR-2's radiator, sitting for 30 years rotted out the whole bottom. It was twice the amount to recore it then buying another aluminum radiator, like the one in my TR-3.

[DavidApp]

As far as I remember the Yellow plastic fan will hit the cross tube between the suspension towers if it is not reversed. I had to reverse mine when I fitted that tube.
There is just room to get the fan belt on but you have to feed it past the fan blades.

How did the shims get trashed?

David

Thanks agin!! Randall.

I removed the fan, installed a new shim, they sure get trashed when you tighten the bolt. Was now able to tighten to 120#, that's as high as my torque wrench will go. You are right as the gap I was addressing was between the edge of the collar right at the timing cover.

Why does R.F. recommend installing the yellow fan backwards, unless you buy one of the special spindles. I assume it would put it to close to the radiator?

Dick