TRI Z correct compression tester & leakdown tester

[this old rz]

Just bought a old Tri Z, need to find out condition & tune up. 1st thing 1st. Compression & leakdown. (bear with me folks I'm budget restricted...lol)

1st time trying this. I bought a inexpensive compression kit from HF. I did a test on the Tri Z and ir reads 90 lbs.?

Now I know that would be considered very low...Mt question : Ive read on several vintage tuners websites thst a "specific" compression tester is required, with a valve in the end?? Is that true?

The length oh the nipple on my tester is about 1/4" shorter than my spark plug. So volume wouldnt be the same.

Yea I know its a HF tool, (but would it be that far off? ) From what I understand I want around 150LBS.

Also can anyone recommend a CHEAP leakdown tester..that I can build or buy..that I can obtain Reliable readings from.


Disclaimer. lol. IM GOING TO BE ASKING FOR ALOT OF ADVICE & HELP FROM PEOPLE MORE EXPERIENCED THAN ME, ILL NEED HELP WITH THIS. THERES ALOT TO LEARN

Thanks!

[YTZ drew]

I wouldn't think that the length of the adaptor being a little bit short wouldn't make a significant difference in your compression reading. That being said, 90lbs is very low. Does it even start with that compression? As for a leak down tester, you could probably cobble one together pretty cheaply using an expanding rubber freeze plug for the exhaust port, a scrap of steel plate big enough to cover the reed cage (intake boot removed), a valve stem in the metal plate, and a foot-pedal style bike pump with a gauge. Not fancy, but would probably get the job done. I'm thinking you're going to end up doing a top end and a pair of crank seals at minimum.

[3 Wheel Drive]

Heres a thread on leak down testers and how to make one:

http://www.3wheelerworld.com/showthread.php/96856-Make-a-leak-down-tester-for-about-20