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Rebuilding My T140V Engine

13K views 108 replies 11 participants last post by  Buckshot1 
#1 ·
Howdy Folks,
Been tearing down my T140V engine that I have in my 70 Bonneville. The barrel and head are at the machine shop (Raber's Parts Mart) in San Jose, CA. They told me the head needs new valves, guides, springs and seats. They said the cylinders need to be bored .040 over. Cost? = $1450.00. Ouch!!! Oh well, it has to be done and I don't know anybody better that can do it.

While the machine shop is busy with the head and cylinders I'm proceeding to split the cases and pull the crankshaft. Just about ready to pull the engine out of the frame but still need to get that nut and gear of the crankshaft on the timing side. Also noticed in the manual that the gears on the camshafts should have threaded holes in them to screw the puller bolts into. My gears don't have any holes in them at all. Hmmm???? Hopefully they'll pull off by hand!???

I also have my tank and fenders over at the painters and should be getting those back any day now. At first he said that he'd have them finished be April 7th and I made the mistake of telling him I wasn't in a hurry. I thought maybe the following weak he'd have them done but didn't hear from him. He finally called me last Wednesday and left me a message saying they've been primed and the red is painted. He thought the scallops would be painted the next day but it was depending on how many insurance jobs he had coming in. So I guess he's doing them in his spare time. As you can see I won't be ready for them for quite a while but just kind of itching to see what they look like.

When I took my primary cover off I notice that the primary chain was real lose. After a closer inspection I noticed that the new tensioner I put on about a 1000 miles ago was broken. The two curved ends on the forward end of it snapped off. What the heck would cause that? I check the chain for wear when I installed it so didn't have to put a lot of stress on the tensioner to get the right tension on the chain. Hopefully it was just a defective tensioner and I wasn't doing something else wrong.
 

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#2 ·
Okay, I got three of the four gears off and it was not easy getting the intake gear off. The exhaust gear and the idler gear came off by hand but that darn intake gear was a bugger. It looks like the intake and exhaust gears have threads around the outside of the center piece. (I wonder what kind of a puller works with that situation?) Even if I did have the correct puller it wouldn't have work without a lot of work because the previous owner of the engine screwed up the threads. Anyway, I ended up making my two bolt puller work by grabbing the under side of the gear from the outside with two nuts screwed onto some all-thread. I had to grind down one side of the nut to fit between the case and the gear.

Hey, it was hokier as hell but it worked.
 

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#5 ·
GrandPaulZ: Hmmmmmm... I heard Raber's was CLOSING their shop to concentrate on sales?
I think they just stopped servicing bikes. I don't think you can take your bike in there anymore to have new tires put on or have the oil changed and that sort of thing. The machine shop is still open in addition to selling parts but think that's about it.
They make it hard to do business with them because they have a terrible website and they only take phone calls on Tuesday and Friday between 11 and 6:00 and on Saturday 10 to 5:00. They're closed on Sunday and Monday. On top of that they are not cheap!

I want to support them and sometimes I don't mind paying a little more hoping it will help keep their doors open....Gary
 
#6 ·
WOL: I believe those gears with the threads on the centre boss were used on the earlier 650 twins with the "dry " frame" up to 1970 - (maybe even later) - there is a special puller - but you dont need it now anyway

Hi WOL,
Although this is a 76 T140V engine, when I got it, it had 64 outer trans cover on it and an older timing cover. I've since switched them out. So you're probably right and I wouldn't be surprised if the timing gears aren't original. This engine came new with left hand shift and one of the PO's converted it back to a right hand shift. With the old 64 outer trans cover there wasn't a filler hole in the cover like the newer models so I couldn't fill the transmission very easily. I had to fill the trany through the clutch cable entrance and would have to take the cover off to replace the cable.

Now off to see if I can get that gear off the crankshaft with another hokey gear puller of some sort. If not I guess I'll be buying one - maybe at Raber's if it's not to far out of reach.
 
#7 ·
that crankshaft gear is very close to the casing not much room to get a hokey puller in there -they tend to be a good fit and rarely slide off without "encouragement"
the correct puller does the job with ease - but not cheap -- wasnt cheap ## years ago when i bought mine
 
#8 ·
After looking at the gear again and contemplating what a hassle it would be to try and make a puller I called Raber's and ordered a new puller today.

While I'm waiting for the gear to show up I pulled the engine today AND, I got my tank and fenders back from the painter today. The color turned out darker than I thought it would. Oh well, I'm still pretty happy with it and glad to have the painting finally done. Hopefully it'll look better in the sunlight (raining all day here).
 

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#11 ·
My gear puller showed up today from Raber's. I was surprised to see it since I just ordered it yesterday.

The right puller sure makes things a lot easier. The gear came off with no problems. Now, to get those cases apart. Hmmm where'd I put that big hammer??? Just kidding but looks like I need another puller. Remember that old gasket sealer material called "Gasket Cinch"? It looks like that is the stuff the previous mechanic used on the mating surfaces. I wonder how hard that's going to make separating the half's?
 
#13 ·
Success!!! I got the cases split and the crankshaft out! I ended up using a rubber mallet and they came apart without much of a problem.

The bearing surfaces looked good to me. I don't see any groves or discoloration on the surfaces and did not feel any slop in the rods. So thinking that everything is good and I'll just replace the rod bearings.

For the engine sitting for so long and for me not knowing what the history is on it, I think the engine internals look pretty clean. What do you guys think??

Now, to get that sludge trap open!

Gary
 

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#15 ·
So thinking that everything is good and I'll just replace the rod bearings. What do you guys think??
I see evidence of a previous rebuild, multiple punch marks on the sludge trap, pin punch marks on top of at least one of the crank cheeks...

That crank needs to be carefully measured with a micrometer for the proper bearing shells. My guess is they will be at least first undersized, MAYBE second (2 punch marks, .020?)
 
#17 ·
Going down to the shop and see if the existing shells have any indication of what size they are. I was watching Lunmad's video on utube last night and on the back of his shells it showed they were standard and made in UK. Curious to see if mine have some kind of indication on them.
 
#20 ·
Yep they're in the parts book and I think they're also the standard shells because the parts book said they are also available in .010 and .020 undersizes. So I'm thinking those will have separate numbers but the book doesn't give them.

Good to know the crank hasn't been turned of screwed with to much.
 
#22 ·
Thanks WOL!

I just went down to the shop again and took out my Harbor Freight mic and it showed the journels were within spec. 1.6235 to 1.6240. Actually one measured 1.6300 so can't really trust the mic. Think I paid $10.00 for the mic so can't expect to much from it.

After watching YouTube on a guy using plastigage, it looked like he was measuring the clearance with the shells in place. For some reason I was thinking they would not be in place.
 
#23 ·
I got the sludge trap out today and was pleasantly surprised to see that there was practically nothing in it! Just about a 1/4 teaspoon full of sludge near the plug and that was it. So somebody definitely had this apart not to long ago.

I spent about an hour and a half flushing the crank out with solvent and a bottle brush until it was clean as a whistle. Now all I have to do is wait for my new rod bearings to come and for Raber's to complete my valve job and rebore.
 

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#24 ·
Hi Gary, The shells are in place with plastigauge. Do not allow rods to rotate on journal during plastigauging. Hold them steady. Wipe oil from journal & shells before plastigauging. Always remove the squished plastigauge. Also make sure all oil is wiped from back side of shells & rod before installing shells on rod.

Use non lock nuts while plastigauging. This saves the actual lock nuts for final assembly.

During final assembly oil shell faces & journals. Then feel rods rotate very freely. Fill crank with oil using a pumper oil can until you see oil emerging from sides of rod big ends.

Be sure you get the Torco TBO break in oil from Rabers to break eng in with. Lube rings & cly with the TBO on assembly. Get 4 qt so you have some spare oil. 30 or 40 wt depending on the temp when you'll be breaking it in. Ask Michael Raber.
Don
 
#26 ·
TR7RVMan: Hi Gary, The shells are in place with plastigauge. Do not allow rods to rotate on journal during plastigauging. Hold them steady. Wipe oil from journal & shells before plastigauging. Always remove the squished plastigauge. Also make sure all oil is wiped from back side of shells & rod before installing shells on rod.

Use non lock nuts while plastigauging. This saves the actual lock nuts for final assembly.

During final assembly oil shell faces & journals. Then feel rods rotate very freely. Fill crank with oil using a pumper oil can until you see oil emerging from sides of rod big ends.

Be sure you get the Torco TBO break in oil from Rabers to break eng in with. Lube rings & cly with the TBO on assembly. Get 4 qt so you have some spare oil. 30 or 40 wt depending on the temp when you'll be breaking it in. Ask Michael Raber.
Don
Hi Don,
All good advise, thanks!

I think I'll make some kind of jig to hold the rods steady while using the plastigage. I'll probably drive down to Raber's and pickup my barrel and head and get all the other little stuff I'll need to put it back together. Like Viton O-rings, Torco oil and gaskets.
 
#31 ·
Wow! That's really good to hear about your thoughts on the paint job. I think maybe I'll keep it for a while and maybe it'll grow on me. And yes I was going for the Astral Red color.

It'll be interesting to see what the plastigage shows. First I have to get that jig built to hold the rod steady. I'll work on that today.
 
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