How To Pressure & Vacuum Test A 2 Stroke Engine

Рет қаралды 31,106

2 жыл бұрын

How to do a pressure and vacuum test on your 2 stroke engine and why it's so important to do so. It's an essential mechanical diagnostic step in servicing and repairing your 2 stroke engine. It doesn't matter if it's a chainsaw, motorcross bike or an outboard, the process is all the same!
TOOLS I USE:
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Mityvac Pressure & Vacuum Tester - amzn.to/3vysI3V
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No-spill gas can - amzn.to/3TDfWcb
Any links to products are likely to affiliate links and I may earn a small commission from qualifying purchases with no additional costs to you. Thank you!
#stihl #echo #husvarna #chainsaw #2stroke

Пікірлер: 69

@VintageEngineRepairs Жыл бұрын

If this video helped you, please consider clicking on the THANKS button above to support my channel 🙌

@markluxton3402 24 күн бұрын

What is Permatex #3? Nothing comes up on Permatex nor Amazon for that name.

@markluxton3402 24 күн бұрын

What is Permatex number 3? Not on Permatex web site nor Amazon???

@billbyrd9845 Жыл бұрын

I'm a 77y/o retired motorcycle mechanic, and I could not have done better in explaining these things. Well done!

@VintageEngineRepairs Жыл бұрын

Very kind thank you Bill!

@ProSaw70 2 жыл бұрын

Good video Tom. Vacuum is measured in inches of Mercury. InHg. 👍🏼

@savage22bolt32 4 ай бұрын

remember the mercury filled Carb Stix?

@THEMOWERMEDIC1 2 жыл бұрын

Greetings from texas, brilliant demonstration! Liked and subscribed!

@garymcmullin2292 Жыл бұрын

you sure have it right, well presented. You are undoubtedly a class A mechanic as you pay attention to detail and proceed in an orderly manner. Disciplined mechanic. Thanks for a valuable info video.

@VintageEngineRepairs Жыл бұрын

Thanks for the kind words, I’m glad you enjoyed it!

@Jorge-de2ny 2 ай бұрын

Totally agree

@ZingaraJoe 2 жыл бұрын

Excellent presentation, I recently got a pressure vac unit like yours as shops in the area do not use them. Lots of trial and error and as a customer I don't like paying for the trial and error. Had a piston go in a Stihl and I knew it was not lacking oil in the gas, though maybe stale gas. Lugging with dull chain is another possibility but first rule out vacuum leaks.

@BrucesShop Жыл бұрын

Right on. I thank you Tom. I learned more about the vacume test for crank seals.

@VintageEngineRepairs Жыл бұрын

Thanks for stopping by Bruce!

@sonofthunder. 2 жыл бұрын

i have a 034 super,and regular 034,and a donor 034 rebuilding to 036...48mm,gathering the seal ,bearing tool,case splitter,spark plug port test adapter, and carb test plate, i did get a cheap ebay vac ,pressure tester,thanks for the video,soon ill have the donor repaired

@klydolph2 Жыл бұрын

I replaced the crank seals, put on a carb kit on my approx 15 years old Stihl MS250. Replaced all fuel lines and filters. Now it runs much worse than when I started. It wont idle properly. I have tried adjusting the high and low jets and the idle screw for hours. It idles fine after starting - then when I use it for a minute and it goes back to idle it will stop. I turn up the idle speed, but then the idle will be obviously too high. I ordered a pressure and vacuum tester today. Thanks a lot for the video.

@davidmech2956 2 жыл бұрын

Brilliant information. Thank you.

@swordfish1120 2 жыл бұрын

Good video. I just bought a Mityvac and spent the better part of an hour trying to seal a Stihl 193t. I kept getting leakage but I couldn't locate it. I finally found a small hole in my impulse line. I did have low compression which is why I wanted to do the pressure and vac tests. Can a hole in an impulse line cause lower compression? Can the Mityvac be used to test the rings?

@ericwhitfield8475 2 жыл бұрын

Great video, best wishes.

@VintageEngineRepairs 2 жыл бұрын

Thanks!

@garrydeimert7397 7 ай бұрын

Nice presentation my friend easy to follow for us old muckers 😅

@VintageEngineRepairs 7 ай бұрын

Thank you! :)

@barney1941 Жыл бұрын

i just received the mighty vac mv8500 kit. now i have to figure out how to use it! thank you fine sir, a masterful tutorial! bravo! i collected 3 stihl 026 saws over the years that need work. i'm too old for dirt bikes, finely tuned chainsaws are the new hobby. thanks for the well explained tutorials. what brand of seals and bearings are quality? (if you are a chainsaw guy) i'm new to chainsaw parts procurement.

@VintageEngineRepairs Жыл бұрын

Great to hear! The mityvac is fantastic. If you want the best, go oem. If you don’t mind using aftermarket visit a bearing and seal dealer. Don’t buy from eBay or Chinese retailers. Their quality control is poor and you’ll likely end up with a leak.

@breikowski 9 ай бұрын

I was able to use the hose from my compression test kit. Had to remove the valve to open the line.

@breikowski 9 ай бұрын

Did not look forward to hollowing out a spark plug then rigging in a barb fitting making it sealed tight. Glad I was able to avoid it.

@VintageEngineRepairs 9 ай бұрын

Awesome! Good work

@RYANINBODEN1547 6 ай бұрын

Question. I have a DT100 and I've done a bottom end swap (cracked case was reason) The old bottom end with top end still ran okay but when I put in new gaskets and did a swap i put my hand over the carb and i feel ZERO suction and no gas getting on my hand. It is 100% not a top end or carb issue at this point I don't believe and it has amazing compression and consistent blue spark. Had to swap points plate and flywheel for it but other then that it's all original. Just wondering if this would be a crank seal issue or what the matter could be.

@VintageEngineRepairs 6 ай бұрын

Yep, without a pressure and vacuum test you’ll wasting your time. 👍

@treecycle4631 Жыл бұрын

Is the spray bottle you use for the soapy water a special purchase or just a generic bottle from some previous life?

@VintageEngineRepairs Жыл бұрын

It use to have foaming soap that I got from the BBQ Section of Bunnings for testing gas leaks :) edit: I actually brought it because it was a small compact bottle. Now it just has dish soap in it!

@bostonmountain Жыл бұрын

Thank you so much for sharing your deep knowledge. I'm linking your video to my FB page, and encouraging my friends to Like and Sunscribe. #StayAwesome!

@VintageEngineRepairs Жыл бұрын

That’s awesome thanks!!

@willdubeast88 9 ай бұрын

Air leaks can cause an engine not to run at all, right? Everything I read online says that the engines just won’t run right. I got a red max ebz 8500 that won’t run. It’s got fuel spark and compression, but is failing pretty bad and pressure and vacuum. So thinking it may be that

@VintageEngineRepairs 9 ай бұрын

It can cause it not to run, yes.

@menditman2004 2 жыл бұрын

Great video, I’m into small engine but have never done this you video has explained it well. Have you got a link for the tool? I’ve just subbed your channel. I do have a channel myself if you have a moment please take a look. Thanks 🙂👍

@menditman2004 2 жыл бұрын

@@VintageEngineRepairs Hi I think I’ve found it, I’ll get one ordered it’s will be a very handy tool for me to have, thanks again for the video🙂👍

@justinf1343 3 ай бұрын

My daughter had a 2006 3 cylinder VW Polo (terrible engine) valves were always burning out and a leak down test showed me which cylinder was the problem.

@VintageEngineRepairs 3 ай бұрын

Yep :) leak down, on a 4 stroke is very handy!

@joebrighton1075 Жыл бұрын

Can you please tell me what the adapter is called that you screw into the spark plug hole. Can’t find one anywhere, and everyone I ask doesn’t know what I’m talking about. Kind regards

@VintageEngineRepairs Жыл бұрын

Sure Joe, I made one from a spark plug! Cut the metal crimp off around the porcelain and it will seperate from the metal. From there remove the crush washer, add an o-ring and Jb weld / epoxy in a barb and it’s done!

@joebrighton1075 Жыл бұрын

Thank you very much for replying, off to the shed to find an old plug 👍.

@dinhomaquinaseferramentas4047 Жыл бұрын

How did you make this adaptation in this sparkplug

@VintageEngineRepairs Жыл бұрын

Yep!

@EndreSzabo-Azabaj_hogy 5 ай бұрын

Hi could you post a link where to buy this tool? Thanks

@VintageEngineRepairs 5 ай бұрын

Hey, I don’t have one, just google mityvac 8500 👍👍

@t008mx 2 жыл бұрын

how dd you remove the internals from the spark plug , have tried a hacksaw but getting nowhere fast

@TheLawnmowerLady 2 жыл бұрын

I chiseled away with an hammer and punch to clear out a plug to make a piston stop. It was a bear.

@jerrysoutherland662 2 жыл бұрын

I use a old compression gauge hose,,cut the hose to length,and use one of the accessories that comes with the mityvac.I also use a golf tee to plug the impulse line.

@VintageEngineRepairs Жыл бұрын

kzfaq.info/get/bejne/jdubgpySydyUk6c.html

@t008mx Жыл бұрын

@@VintageEngineRepairs Thankyou so much for making this video much appreciated .

@yvonblanchette3682 10 ай бұрын

My engine is stripped like yours, is it normal that without plugging the two portes and rotating the shaft I get vacuum at the plug.?

@VintageEngineRepairs 10 ай бұрын

Without plugging what two ports?

@yvonblanchette3682 10 ай бұрын

@@VintageEngineRepairs the carburetor and the exhaust

@chenangokid 2 жыл бұрын

should it hold for how long ?

@VintageEngineRepairs 2 жыл бұрын

About 30 seconds I test for.

@chenangokid 2 жыл бұрын

thanks for the reply. i recently tested a chainsaw. and it held a few minutes. but i left it on and came back later and it bleeded down great videos.

@VintageEngineRepairs 2 жыл бұрын

@@chenangokid pleasure, sorry for the delay, it’s easy to miss comments! Tiny leaks like you have that hold but will eventually bleed will not cause an issue, other than if you’re a perfectionist and want to find it lol. Ideally it’ll hold indefinitely, but most all manuals specify a short holding period something around 30-60 seconds.

@robbidi123 11 ай бұрын

No need to build a custom tool. A compression air hose nozzle will screw right into the sparkplug hole. Both are 14mm with same pitch.

@VintageEngineRepairs 11 ай бұрын

That’s great when you have the right size adapter / the kit, but the ease of this for when you don’t is handy for people to make at home very affordably.