Bonneville America Forums Forums General Motorcycle Forums Other Bikes T120 from He!! update

Wipe down the bores with WD-40 and paper towels till they come out clean (removing the grit from the honing stones)then put some 30 weight on the bores and rings.

Wrist pin bushings replaced...along with what seems like everything else...Geez, not getting any return yet...This better have a good outcome!

All back together, reached goal of starting the engine yesterday. She runs rough, but has good oil pressure. Down to final tweeking...setting timing with a strobe, and tinkering with carbs. Gearing seems to be mis-clocked, as 2nd gear is as low as she'll go...No biggy, will have to pull tranny cover and re-position shift quadrant one notch. Here's some pics with my "spray bomb" paint http://i294.photobucket.com/albums/mm88/KimmyA70/PICT0206.jpg?t=1269345121

http://i294.photobucket.com/albums/mm88/KimmyA70/PICT0205.jpg?t=1269345236

Sorry, getting the link here is best I can do, my son just left for school...

I sold this sometime ago
I was just getting tired of some little glitch,that needed a fix or a tinkering with, pretty regularly.Heres hoping.The BA isn't this way. This "70" bike was "new" about every way also.course i failed to mention, it was getting harder for a new hip to k/s. and it started great! jmo

Completely done tonight...took 3 afternoons to get the gearbox shifting quadrant straitened out to where it would shift to all 5 gears, she runs great, starts on first kick...Jeez what a project...

Basically at the end of my rope with this bike...After getting her all back together, for like the 5th time, the forward push rod tube continually leaks profusely. I've removed the cylinder twice now for this problem, and thought I had it fixxed yesterday, as every gasket and seal has been replace twice now. I took her for a short 3 mile ride, and no leaks. Decided to take her to the store last night, and looked down, and seen that the stupid forward push rod tube is ****** out a steady stream AGAIN...I've got nearly, what seems like over $4000 in this piece of crap, and it still is'nt right. I simply don't know what to do with the bike right now, as it's sitting in the garage, and will remain there until I come up with a solution. Very frustrating, and I advise ANYONE that's thinking of taking on a restoration project of one of these bikes, to reconsider, because they are EXTREMELY difficult to get right.

Hey Mark,
I've found Plewsy's videos very illuminating as I work on my 64:

http://www.youtube.com/watch?v=m1zxtrTbwJ4

On the other hand, I share your misery as I found this yesterday:



now it's off to the machine shop (with money I don't have) to see if my local machinist can weld and surface this bearing boss so I can start reassembly.

That front tube leak could be a couple things. Were the tappet blocks out? If so it is very easy to roll the O ring that seals that during installation. There is oil pressure there too that feeds the Exhaust tappets. That is more likely than the tube since there is no pressure in the push rod tube and oil just drips back down there on it's way back down into the sump.Also there are a couple kinds of tubes and tube gaskets , be sure you have the correct tubes and gasket combination, those are easily swapped around over the years especially if the engine was done before and maybe an older head was used. I have never had a push rod tube leak much. Had a couple seep just a little but so little I ignored it and rode it.

Ed, that has to be one of the first visibly cracked cases on a unit twin I have seen. Had a couple that showed cracks when magnafluxed. Seen that and worse on old HDs and on pre-units before they started to use bigger bearings (early 50s and before). That crack looks like a fairly easy fix as long as there are not hidden cracks and you have a good machinist.

It's not all the way through so I have hopes it can be welded and then resurfaced without too much drama.

04/14/10..Still have'nt decided what to do at this point. The 3 state ride is the 22nd of May, and I just don't think the bike is gonna be ready. I took it for a 40 mile ride yesterday, and oil simply coated the front of the engine, and lost nearly a pint out of the oil tank, that's cracked at the swing arm weld. Other than that, the bike ran perfect...Will simply have to pull the cylinder AGAIN, and take to an expert, maybe NDT the tappet guide for cracks, then see if I can have the frikkin tank welded too, but not likely to happen before the rally. I'll just cancel and bring my favorite Triumph to the Georgia Rally....
Ed...I think that can be fixxed pretty easy...I just hope you dont run into HALF the problems I've had...

Mark's got two really sharp operations close at hand: British and American in Doraville and Rodi's British Bikes in Winder. Randy at B&A is very good and Richard at Rodi's has been a Brit shop mechanic since the late 60's.

Unfortunately you MUST remove the cylinder to remove either one of the PRT (Push rod tubes). They are wedged between the bottom of the cylinder and the cylinder head, so yeah, the cylinder head AND cylinder will have to be pulled yet again. The good thing is that now I can do this entire drill in under 2 hours, that's off AND on with everything, so no biggy.. The frustration is finding a fix. I will take the cylinder off, and take it to someone and have them put the tappet in after checking for cracks...Just time at this point.

No you don't have to remove the cyl to remove the tubes just the head. You only have to remove the cyl. to remove the tappet blocks. The push rod tubes are between the tappet blocks and and head, the head pushes down on them to seal on the tappet blocks. Once the head is off you can remove the push rod tubes leaving the cyl. in place. It would be best to have someone who knows take it apart to see if they can spot the issue but that's up to you.

I stand corrected Dog...I meant to say cylinder head, your absolutely right. Stupid midnight shift has me waking up on my days off at like 4 am...So downstairs I go, take cylinder head and cylinder off in like 20 minutes, remove exhaust tappet, and sure enough, o-ring is destroyed AGAIN. Installled new o-ring 3 times, and removed to inspect each time, o-ring still looks new each time. Installed yet another new o-ring (I have quite a collection from all the gasket kits I've bought) and decided it's good for another try. Took cylinder and all down to my buddy's house, who has ALOT of experience with these, and he pointed out the fact that the "wedding bands" are actually cone shaped from over crushing. He gave me the only new one he could find in his shop, I'll need one more...this may have contributed to the problem somehow..Having frame TIG welded tomorrow hopefully by a co-worker that's REALLY good with a welder...Im not gonna let this bike win...I will succeed!!!

I would have bet on that O ring from what you described, glad you found the issue. That O ring is very easy to damage during assembly. On the later models such as yours that has oil pressure too , earlier ones don't.

Mark,
I've studied my own project enough to be able to repeat this with some confidence: if you'll experiment placing the 'o' rings (and you have an assortment of thicknesses) on the tubes until you can just fit a 1/16" drill bit between the head and the gasket when it's floating on the pushrod tubes that spacing will give the optimum crush factor.

I'd bet, though, that you need new 'o' rings on the tappet blocks because the oil pressure in the pushrod tube is so minimal. Think about it, that feed comes from the rocker boxes and they're a drip feed from a 'Y' in the return line; the tappets are getting 80 psi. That means pulling the cylinders to replace the gasket on the tappet blocks...a good job for our friend Randy at B&A.

The exhaust tappet block is the only one that gets oil pressure.

Exactly. That's where the leak is, isn't it? Or, did I read the post wrong? However, I must concede that Ian has years of experience with these engines and I'm just on my first.

Just seems like false economy not to replace both when the cylinder's already off and you've gone to the trouble to source someone with that specialty tool.

That's correct, the exhaust tappet is the only one that's pressurized. The Guru's seem to think the oil pressure is way too high(70 psi at idle). Took a little off the spring in the Oil Pressure regulator, now she's sitting at about 60 cold, 25 psi hot, so that should solve that possibility. Welder fell through...taking the bike to work with me Tuesday night for a TIG weld. Primary cover still producing quite a puddle under the bike. took that BACK off again too and surgically cleaned both surfaces...Thinking about having that stupid thing TIG welded too

You will lose your mind trying to make that bike not leak at all. It should run 80psi.

Tank welded, but still seeping. Applied JB Weld (hated to do that), and put her all back together...Fist kick, she idled like new. Took 60 mile ride with Kimmy bringing up the rear, and she ran flawlessly. The tank is still dry, but the forward (exhaust) push rod tube was wet, but not running. Hopefully it wont progress. Had a blast cruising the west Georgia countryside...

JB weld still holding, but the front push rod tube (PRT) has advanced to another unacceptable running leak, after the 4th attempt at stopping. The first 7 to 10 miles, the PRT area was dry, and I thought I had it licked. After the 60 mile ride Sunday, it was a little wet or damp, then yesterday, I had to turn the bike around and head back home, as oil was flowing AROUND the cylinders, down the primary, and puddling under the carbs. Im either using the incorrect o-ring, or the PRT or cylinder base is cracked. Will removed cylinder for the 5th time Sunday morning hopefully, and not break another ring, as Im fresh out...This bike has easily exceeded my patience and is beginning to make me look foolish, don't ya'll think?

So is it still leaking after replacing the exhaust tappet block O-ring or did you skip that idea?

It is starting to sound like you have a faulty part in the mix, something bent or worn. I have seen them leak a little after some time but those tubes usually don't leak at first and when they do it is rarely a stream unless the rubber had dried out and in your case the rubber is new. Thought you finally had it beat.

Mark:

I had the same problem with a '70 Bonnie that leaked (poured out ) of the exhaust tube. The tappet block should fit tightly (forced into the cylinder base). Mine was loose enough to push in by hand. Most likely either the tappet block was worn or the cylinder base was enlarged. After repeated attemps (like you) I used an adhesive called 'YamaBond' and gooped it up making sure not to block the oil feed holes. Sealed her up and stopped the leak!

YamaBond is a grey gasket sealer that is very good that was recomended for the cases.

For the leak on the Primary, all I use is the gasket and coat both sides of it with grease. Makes a good seal too.

Good luck, don't let it get you!

There is a special drift to remove and replace the tappet block as Pokey said you should not be able to remove it or replace it by pushing. If you were doing that then right there is the problem.

Tappet block o-ring removed, and found to be "melted". This is certainly the incorrect o-ring, I have learned. The "Emgo" gasket sets do not come with a tappet block o-ring, and I have been installing a o-ring that is not capable of handling those kind of temperatures. Ordered correct o-ring from M.A.P. cycles, they are in agreement with me. New seals should be here tomorrow, and I'll get her back together by Sunday...

There you go...she'll seal up nice and tight now.

What ya gonna take apart Monday? That tappet O ring is a special material as well as the push rod tube seals to handle the heat. Lube the tappet block O ring when installing so it slides in and doesn't roll.

Mothers day Sunday, will do all this Monday...will need another copper head gasket, as this one has been "annealed" twice now....

Don't forget to put that oil pressure spring back in, you'll be wanting that 80 psi when the O-ring is finally sorted out.

All back together today (Monday). Was plum whooped after over 300 miles on the America Saturday. I got good compression on both, and she fired right up. No leaks at this point, but Im not able to ride her because of the pesky rain....May get to try her out tomorrow. Cheap petcocks leaking like crazy...oh what the heck, another $40...

I can't wait to hear how she does when you can get her out on the road. I'm getting closer now, big motor parts order goes in to B&A tomorrow and the tins went to Vermont this afternoon for paint. Maybe I'll get mine done before the summer is out...

Got up this morning, bored out of my mind, checked all the fluids, tinkered with this and that, rolled her out of the garage, tickled the Amals, and she fired right up, first kick. Oil pressure at 60 and stable, nothing pouring out anywhere. Clicked down into 1st gear and off I go. Onto highway 61 out of Dallas, she's purring like a kitten, and responding with a growl, plenty of response. About halfway up Braswell mountain road, a dull pain develops in my tailbone, which quickly becomes nearly unbearable. Not stopping now though, gonna see what she's got, endurance wise. Onto highway 113 out of Rockmart, I go a little over a quarter throttle, and she responds with a sweet growl, and my helmet starts pulling off my head. The old sportster pipes produce a very neat rumble, and the pain in my tailbone seems far away now, but still very present. I pull onto "covered bridge" road off of 113, and putt past plant Bowen, a massive coal fired powerplant that always mesmerizes me with the giant water cooled stacks. On through Euharlee, and into Cartersville, bike still performing like new. Onto highway 61 south into Dallas and into the garage in Hiram, after about 70 miles or so. No leaks anywhere on the engine, and oil tank still full. Finally reached a point with this bike that I've been after for nearly 3 years now....I've learned just about every aspect of the engine, and now just want to enjoy....I may develop the endurance to come see my friend Ed over in Alabama with it soon....Would make a good day trip for me from Hiram....Glad to have this bike in my Triumph family.

Glad it seems to be sorted out now, I love the old twins that I own.

Good one mate glad to here its running good after all the $hit you had getting it there
They are a lovely bike to ride and treated right are as reliable as any old bike can be
I road my old Triumphs around Aus for years enjoy