Just bought a leakdown tester from Harbor Freight. Anyone have this unit. I've never done a leakdown test so I have no experience with different testers. Is this unit ok? It lists for $39.99 on sale online for $29.99.

HF Leakdown Tester Link

Thanks,
Spoke

i was going to call them, there's another one there for $39.99

http://www.harborfreight.com/cpi/ctaf/disp...Itemnumber=4317

i don't know what's different. if anyone knows about either one, i'm curious too.

I had one of those.
it wasn't great actually

you need a unit that works at 100psi
If I remember correctly the HF model worked at a much lower psi

I used mine once and had inconsistent readings
I actually returned it

I bought one from summit? (don't remember exactly where I got it honestly)
My current one was around 90$, but works great
and had been put on a half dozen motors now.

brant

I have one and it works at 100 psig supply. Thing is, when you set the zero on the percent guage the pressure guage reads about 15 psig.

Just remember to pull the pressure off by rotating the set knob before disconnecting from the cylinder hose or you will move the percentage needle out of calibration (if it's actually calibrated).... The needle will hit the stop and move on the shaft.

There are better units I suppose, but it is functional.... kinda like center console guages.

I just checked those links and both of those units say they have a working range up to 100psi

for some reason the one I bought back then did not...
I kinda remember it was 40psi (maybe 50?)

so I'm guessing it was an earlier model that I had and that may of been part of the problem.... or it may of been a bad one..

overall a lof of the HF stuff works out fine for me.
obviously its not commercial stuff, and you get more defective items
but overall I have had pretty good experience with HF

I have one of theses. Well made, werks good, plastic case and cheap compared to the "real" ones

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...s_promot_widget

OK, I've never done a leakdown test and I can't get good numbers from this thing. The directions don't seem to be correct. Here's what the directions say:

1) Set cylinder to TDC. Duh.

2) connect unit to cylinder plug.

3) Turn regulator til leakage gauge reads "0".

4) Now read amount of leakage on gauge.

5) do other cylinders.


What am I missing? between 3) and 4) there seems to be nothing to do. Seems to be something missing?

If I set pressure regulator without connecting to cylinder so leakage is 0, pressure is about 17psi. Compressor is about 80psi. Then when connected to cylinder, leakdown is about 40%.

I have no idea how to do this properly. The only good thing right now is that it's New Years Eve and I've had a few Jack & 7Up's (quite a few by now) and I can't see my feet!!!

Spoke

1.5 ..... connect unit to air supply

1.75 ..... Set "0"

2.0 ..... Connect to cylinder hose

Kill #3 on your list and go directly to #4

If you are doing this on a cold engine .... your numbers are elevated .... heat expansion has not "sealed" the cylinder (which is why you change oil ... on startup, combustion gasses bypass rings to a degree).

And in my opinion, while I would like to see low numbers what is more important is the tool allows you to "locate" the source of leakage ... leaky valves, worn rings, etc.

Of course, you could ditch the guage and pressurize the cylinder with air (80 -100 psig ... with a flywheel lock in place) and listen at the various aperatures for leakage .... just no fancy multi-colored guage to make you feel bad.

You have to learn to interpert the Chinese, Taiwanese, Koreanese, etc., technical instructions written by rice farmers.

Thanks, I tried these extra steps and got numbers in the 30-40% range. All cylinders were about the same.

I can't warm the engine since it's connected to nothing with no carbs. I did notice that the numbers went down a bit after spinning the engine a few revolutions by hand.

So ideally a leakdown test should be done on a warm engine? I guess the same is true for a compression test?

In an ideal world .... YES