T500 center crank seal

[RossB]

Hey Guys
Just got my 74 T500 on the road today new outer crank seals,rebuilt oil pump, lines airless ( Thanks Fred!) Runs great! BUT.... Blowing oil/smoke at higher revs coming from crankcase made dipstick checked before and after ride some oil missing.If center seals were bad wouldn't the bike run poorly?
Both sides smoke the same amount,might do leak down test, bikes got 10K on it and sat for 30 years.
Running out of Love,Craigslist here I come.
Peace

[Vintageman]

If center seals leak a little it won't affect performance. But since the center bearing is oiled by gear box, oil weeping past seal will cause smoke as you noted.

The right thing to do is take out crank. Not to be negative you may also note the con rods have rust stripes where needle bearing had set still for many years. I had both issues and spilt cases 2 times (first was broken kick starter).

If you sell what state are you in?


There is one possible (small chance) miracle repair. Buy a couple 8 oz bottles of Blue Devil Seal conditioner or ATP-205. Mix with a Diesel fuel and fill the gear oil case to the max with the mixture. See how fast it weeps into case by removing drain plugs under each cylinder. You can also fill this area as well with mixture. With seals completely submerged let is set a few days.

If it leaks by seal very fast it is probably broke and not just dry.

[RossB]

Morning
Thanks for the encouragement I live in Redding Ct might be nice winter project have a lot into her already
tires,shocks,chain/sprockets,battery,air filter,rebuilt oil pump new banjo valves (good one's),etc.......
Thanks for your help

[Vintageman]

I am in Southern NH so if you do get sick of it .

When you own an old bike, want to use it reliably, you eventually have to go through everything. The T500 engine like the other suz twins is one of the easier ones to work on relatively. A few weekends of your time you have motor out fixed and back in. You'll have to wait weeks for parts and crank service, shipping time and probably have a few more hundred bucks if not more into it depending what it needs. Good winter project yes.

If it was me I would throw even more money at it and get a set of early cylinders and fresh bore while I was that far (my money tree should bloom again next spring!). They definitely de-tuned the bike 73 and on... maybe to make GT550 look better ...maybe not. The 69-72 cylinders alone wake it up and matches the old period reviews of when the bike was rated high. One of the better things I did to my 1975M. Dang keep money going an use Wossner or the like forged pistons and you can rev it up with no worries maybe of cracking skirts (sure later style NOS decent too... no need to rev it too high). Just $$$ and time.

Sell some (bfore people who think theuy ar ecool are long gone), save your money instead and have enough to buy either a new miata,z, Focus ST, GTI, Camaro, Mustang,etc, plus a Harley... wife keeps telling me I am thinking she may be right. Money/time pits

Good luck

[RossB]

Morning
Looking for cylinders right now! I'm going for it! I did a RD400 last year so easy, lots of parts available got the
bike for free, 5K later nice bike. Good chance to look at tranny getting some false neutrals.Maybe headers?
Thanks
Ross

[RossB]

A guy on EBay has a complete set for 72 T500 cylinders, heads,pistons gaskets all machined for $800.00 Is it worth it,cause all this money I have is burning a hole in my pocket!?(not)
Check it out thanks!

[Vintageman]

Don't believe what you read.... I think those are the later style. You can tell looking at intake and they should have no aluminum intake divider.

You can find these cylinders much cheaper ($100 to $150), if you are patient. Make sure you get the early style.

But you need pistons and a bore job. Engine shops will do the job for $40 -50 hole... but usually guys want more and if you have to ship $$$. Pistons, well there are the Crusin mans up to Wossners. Gaskets, wrist pin stuff.

let's see

$150 (pair of used jugs)
$100 ( bore job)
$225 (Wossners)
$75 (mics)
------
$550.00 that's ~$140 per extra horsepower

You can do better if you are patient.... maybe you get a set of cyls cheaper or with bore OK or good deal on NOS pistons/ring etc if lucky reuse your piston and opt for new set of rings.

If you like to ride em it will make you smile even harder... what's that worth

[jabcb]

The ad says the cylinders were taken from a 72 T500. But the 72 T500 didn’t necessarily have its original cylinders.

If you want just the early cylinders, then its worth calling Paul Miller.
I needed a left cylinder for my 69 T350 because some PO trashed it, and Paul had one.

[RossB]

Thanks guys
Pulled engine last night so easy to work on,took heads and cylinders apart they look great
Super clean no scores little carbon on top of Pistons. I have all winter to keep my eye out
For some cylinders didn't know about the dividers thanks ,can I use my old heads?
Going blast the frame and paint or Powder coat,rear wheel has a little hop in it have to
Figure that out.
Thank you!

[Vintageman]

You can use your later heads just fine.

jabcb was the left T350 Cyl NOS or used from Paul?

[jabcb]

You can use your later heads just fine.

jabcb was the left T350 Cyl NOS or used from Paul?

It was used.