Triumphrat

snortindog

Just bought my first Triumph, a T140E, 1979. 10,000 miles. PO said it smoked, needed new rings (also said clutch slips). It was sold in crates.

What I found so far scored/scratched; pistons, bore, rings, valve stems, tappets, exhaust cam lobes, intake cam lobes look good..

The air filter is incorrect, it does not allow airbox to seal, no rubber seal on filter. It also is too thick to allow airbox halfs to seal together. So it deffinitely passed dirt.

I have the jug off, have not got into the cases yet.

I am wondering what to expect in the bottom end. Your best guess as to whether all of the bottom end bearings, bushings... are junk is greatly appreciated.

I would hate to part out bike. I like the look, and wrenching is therapy for me. But I can't see spending 2 grand more than bike will be worth.

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Triton Thrasher

That cam looks like a victim of running out of oil. Expect the crankshaft big ends to need reground.

If you do overhaul it, you might save a little money by getting the exhaust tappets reground rather than replaced. A good rebore is better than a new barrel, but it has to be done by old bike people. If the camshaft bronze bushes look OK, don't remove them. I would get Kibblewhite valves and guides, even though they're dearer than standard.

Your air filter problem is trivial and you may not even get to the stage of fixing it, if you break the bike and engine for parts.

Snakeoil

I agree with TT. That looks like gauling which is from metal to metal contact, not dirt. Besides, intake dirt should stay above the piston rings and just do damage to the cylinder walls.

Guess you learned to look closer at the parts in the boxes next time, huh. As nice as she looks in the picture, she's pretty ugly inside. Probably owned by a rider who bought lots of polish and fancy riding gear and had no idea where the dipstick was located.

I put about $1200 in parts into my '66 engine, which included new pistons. I had the guides knurled which saved a little there, plus you only have to lap, not recut the valve seats. Crank was fine, but new bearings all around. So add in labor if you are not doing the rebuild yourself, plus the added machine shop work if the crank needs grinding and will probably spend close to $2K on the engine. Maybe more if you live in a large metropolitan area where the shop prices are higher.

regards,
Rob

snortindog

Thanks for the quick reply. All of your advice makes sense.
I definely should have looked at things better.

So around $2k on engine. I would do the teardown/rebuild myself. But I would have to add any special tools/pullers I can't fab myself.

I really can't complain, I've had good luck on many other fixer-uppers.

I have a question for TT. Does the jug need to go to a specialist to be bored? My guy has been doing this for 20+ years, but I am not sure if he has done much with Triumphs.

Thanks for the help

My name is also Rob

Triton Thrasher

The. rebore has to be to the recommended Triumph T140 clearance, which is looser than what modern engines have. It should be honed with a rougher stone than a modern bore, to bed in the cast iron rings. If the engineer doesn't already know that stuff about old engines, he won't believe you and he'll bore it tight, leading to a seizure and he'll hone it fine, so it will probably burn oil ( until it seizes).

It needs to be done by someone who regularly successfully bores Triumphs, BSAs, Nortons.

DAVE M

Doing the rebuild is not difficult provided you read the manual and seek advice from here(or another"vintage" site) special tools would top out at $200 if that.

most people spend more on rebuilds (of the whole bike) than the bike is worth. This isn't a money making hobby.

if your bike is ok cycle wise
but needs engine work, it's better to keep it

whatsthat

Looks like you have a nice T140 there, you didnt say what you paid for it, from the camshaft it sure looks like a lubrication failure, as stated above the motor will need a full inspection and cash injection based on the results but you will have great bike at the end of it, I would hang in there. After the motor re-build, it would be a wise Idea to sort out the Leaky non sealing airbox arrangement to preserve the bores in future.

__________________
" KEEP 'ER LIT LAD "

snortindog

If I do rebuild, I will make sure it is with a veteran Triumph builder, and I now know some important questions to ask!

I did get manuals. I did pay too much, $2,300. There is almost no corrosion on the entire bike. All the chrome looks great. Frame and tank have been repainted, and are in good condition. All indications are the 10k on odometer is correct. Pistons are original.

Right now I am leaning toward fixing it. When the wife asks how many bikes do you need, I always say "Well, there's seven days in a week, one for each day would be a good start!" Just need three more.

I stared and drooled over this model at a local dealer when I was 13. Bet most of you are familiar with the feeling. Love the sound also, almost as much as a triple 2stroke!

dl.allen

Dont feel bad. I did the same thing. Paid too much for an unknown roller so felt married to it and just dove in and rebuilt the engine then kept going and gave it a full restoration. Love it now and runs great. I figure in about a 150 years or so it should appreciate enough to break even. But having fun the meanwhile. I had almost identical looking cams and mine needed crank regrind, camshaft journals, and new mainbearing. Mine must have injested gravel.

Mr.Pete

It's not the worst cam I've seen,and it may still be servicable.It's hard to tell from the photo.The nitrided surface is about 0.017" deep.If it's worn more than 0.010" depth at any point,replacement would be a good idea.Exhaust cam lift is 0.305".Most wear would be near the top of the lobe.Measure from the base circle of one cam to the top of the lobe on the other.If it's less than 0.295",it's probably not good.

If the wear seems less than 0.010" deep,you could stone out the score marks or polish them out with #400 emery paper supported by a flat block.Use a rag or tissues to keep any abrasive out of the crankcase.

If the cam is beyond help,replace it with a 3134 cam from a '70 onward 650.If you use the 650 cam,get the exhaust tappets re-ground to "R" radius (1-1/8").It would also be a good idea to replace the timing-side main ball bearing with the 3-piece roller bearing.

If cam lobes and tappets look OK,you can use them in their original position (on the same lobe) and facing the same direction.Other than that,the tappets should be re-ground (cheap enough).The cam and tappets should be then coated with cam-lube.The engine should be run at no less than 2000 rpm for the first 20 minutes.Avoid any slow cranking before start-up.

The cylinder bores might not be as bad as you think.Standard size is 2.9913"-2.9924".If they clean up with a #180 grit hone and measure less than 2.998" at the most worn section (within 1/2" from the top),you should be fine.I've gotten away with a little more than that,and had good results.A few light vertical dust scores won't cause much harm;better to leave them than to hone it out too big.

You can clean the piston skirts with Scotchbrite to make them look better.If the ring side clearance measures much more than 0.004",it could be better to just buy new pistons and rings.New compression rings measure 0.0615"-0.0625" wide.If the cylinders measure up OK,you don't need a re-bore.Check the skirt clearance at the tightest part of the cylinder,to make sure it's enough.

Check the valve spring seated loads with batroom scales,before you pull the head apart.Keep all springs collars,valves etc in their original order.It is a good idea to cut the valve seats on centre with the guides;they weren't perfect when they were new.The guides should still be good enough,but you could sharpen the tops like a pencil at 120 degree included angle to reduce oil consumption.