donbrew

https://mobiloil.com/en/article/car-...-leakdown-test
For some reason the mobiloil link doesn't work anymore.
This link is very nice.

843de

Nice find Don!

donbrew

I should have credited DrLoch with the find. I just found it was good and the site has some good info.

Oldblue

Great idea, Don thanks for the sticky!

firemangeorge

Not to be picky but I think the title should include "engine". Being a SS guy, I 1st thought it was How To about a turbo system leakdown test.

All in all, a good find and great addition to the sites How To section.

RJ_RS_SS_350

Thanks Donbrew for stickifying this!

I got the leak down tester from Harbor Freight, and while I did eventually get it to work properly, there were a couple of issues.

First, the printed directions were incorrect. As you see in the link in post #1, you need to calibrate the regulator to zero BEFORE you hook it up to the hose going into the cylinder. The printed instructions tell you to hook everything up and then calibrate.

Throw away the included, printed instructions and perform your testing as shown in the link in post #1. OK don't throw them away, just make notes in them, in case the linked-to webpage ever goes away.

So I did that, and still had issues. I was getting readings all over the place. I could not get the "percentage" gauge to stop moving when I was trying to zero it. I found this video on youtube.
The gist of it is that the right hand, "percentage" gauge is good only up to maybe 12 PSI, but the regulator doesn't function well at such low pressure. You have to remove the left-hand (100 PSI) gauge, put a 1/8" pipe plug in that hole. Remove the right-hand (percentage) gauge and install the 100 PSI gauge in that hole.

These were extremely tight, so if you're not very careful, your wrench could slip, damaging the brass shoulders and potentially injuring yourself. 13mm would not fit, 9/16" was pretty sloppy. 14mm is very, very slightly smaller than 9/16" and may work a little better, I don't seem to have a 14mm open-end anymore, so I had to get by with the 9/16".

The pipe plug was $2.59 at the hardware store. A bench vise would have helped with removing those super tight gauges.

I agree, "How to perform an engine cylinder leak down test" would be a better title. I saw "non-turbo" and hesitated, wondering if it was a different procedure for a turbocharged engine.

donbrew

I didn't understand, not being a turbo guy. It never occurred to me that the turbo would also need leak down testing.

Actually I'm more familiar with leak down in plumbing, water and gas.

RJ_RS_SS_350

Thanks Donbrew Here's a link to a homemade Boost tester over at css forum. Thanks SSlobalt.

DrLoch

Good information. You would do that if you were having trouble building boost and wanted to check all the connections and intercooler downstream of the turbo up to the TB.