HOW-TO Pressure & Vacuum Test On A Chainsaw

HOW-TO Pressure & Vacuum Test On A Chainsaw - Leak Down Test

Рет қаралды 127,471

8 жыл бұрын

HOW-TO Pressure & Vacuum Test On A Chainsaw - Leak Down Test
Can't find what's causing your chainsaw to not run properly? You may need to do a leak down test.
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Easy to follow and thorough step by step tutorials do it yourself (DIY) to help you with your broken lawn and garden equipment including snowblowers.
I do my best to teach you how to easily diagnose problems the fastest, quickest and most efficient way with real repairs beyond just replacing a spark plug. These tips are for both the homeowner and shop owner.
Whether it be a handheld, two stroke, two cycle engine like a chainsaw, weed eater, weed wacker, string trimmer, grass trimmer, line trimmer, hedge trimmer, strimmer, brush cutter, leaf blower, or four stroke, four cycle units like a lawnmower, wood splitter, lawn tractor, snowblower, pressure washer, generator or a ride on mower that needs parts installed or replaced, I’m your go-to guy.
My favorite brands of spark plugs are NGK and Champion and are the ones I recommend.
I’ve been a small engine mechanic for many decades and also run my own repair shop so my videos are loaded with tips and tricks that I have learned and want to share with you. You will also find many tool and product reviews from top brands on my channel as well.
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Due to factors beyond the control of DONYBOY73 “The Small Engine Doctor”, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. DONYBOY73 “The Small Engine Doctor” assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. DONYBOY73 “The Small Engine Doctor” recommends safe practices when working with power tools, hand tools, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of DONYBOY73 “The Small Engine Doctor”, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not DONYBOY73 “The Small Engine Doctor".
#donyboy73 #db73 #stihlchainsaws

Пікірлер: 228

@jamesgingin590 4 жыл бұрын

I like how you get right to the point and don't dribble on about things that don't matter. You're the best small engine mechanic on KZfaq.

@reedjose7624 2 жыл бұрын

I know Im asking the wrong place but does anybody know a tool to log back into an Instagram account..? I was stupid lost the account password. I would love any tricks you can give me!

@reedjose7624 2 жыл бұрын

@Byron Kelvin I really appreciate your reply. I got to the site through google and I'm trying it out atm. Looks like it's gonna take quite some time so I will reply here later with my results.

@reedjose7624 2 жыл бұрын

@Byron Kelvin It did the trick and I now got access to my account again. Im so happy:D Thank you so much you saved my account :D

@byronkelvin912 2 жыл бұрын

@Reed Jose Happy to help xD

@num1booger 8 жыл бұрын

DONY, I KNOW WERE ALL HUMAN AND HAVE OPINIONS, I DO NOT UNDERSTAND WHY ANYONE WOULD LEAVE A DIS LIKE (THUMBS DOWN)EVERYTHING IVE WATCHED FROM YOU ALL YOUR KNOWLEDGE IS WONDERFUL FOR US DO IT YOUR SELF FIX IT GUYS.BLESSINGS TO YOU AND ALL READING THISSTEVE IN BEAUMONT CALLY

@donyboy73 8 жыл бұрын

+Steve Hoover jealousy causes people to do that, also other insecure shop owners who don't want people to fix their own stuff

@garyronan5568 7 жыл бұрын

donyboy73 Or A guy that sells new chainsaws!!

@thomasgronek6469 6 жыл бұрын

Big Guy; I was thinking the same thing. If the thumbs down is clicked, a piece of constructive criticism should be left out of courtesy, and for the sake of improving skills and knowledge.

@earllister2513 6 жыл бұрын

Dony, your videos are extremely helpful! I enjoy the detail and attention you give. I have learned a lot from you! Keep putting out videos !

@clubdetennisdolbeau-mistas5971 6 жыл бұрын

A REAL PRO. It's great to see you performing as you do. Thanks for all those vids and keep up the good work.

@drewthornton4684 8 жыл бұрын

the old wizard 998 thanks im new to this small engine thing last year i got a whipper snipper fixed and running thanks to don

@seansysig 8 жыл бұрын

A very clear & concise troubleshooting video that can solve a saws inability to run! Best Small Engine Repair You Tube Channel!

@donyboy73 8 жыл бұрын

+Sean Signer thanks Sean!

@lornaandy969 2 ай бұрын

Thanks Dony, first class as usual. What were the symptoms with this saw??

@billtattersfield2895 5 ай бұрын

Great content thanks

@ralstondaley6448 3 жыл бұрын

Your so professional donyboy73

@seanbrenton55 3 жыл бұрын

Thanks to this video, I did a rudimentary press/vac test with a big veterinary syringe on my 1978 Stihl 031 and was able to rule out the crank seals. ended up being a deteriorated impulse line. Saved me tons of time and money. Thanks, Don!

@carlmiller1034 8 жыл бұрын

Great video Don! Thanks for the thorough detail on how to trouble shoot with the use of the pressure and vacuum tests.

@donyboy73 8 жыл бұрын

+James David thanks for watching david

@bird474 8 жыл бұрын

I'd like to see you do a leak down test on a snow blower/lawn mower! : )

@davidmech2956 2 жыл бұрын

Thank you

@gclaper1234 7 жыл бұрын

Hi I have a question can this be done through to spark plug hole. Thanks Glenn

@SteveRobReviews 8 жыл бұрын

Nice tip Donny . Since I already have an automotive smoke machine I have found it works great as well in testing for all sorts of leaks on small engines too.

@donyboy73 8 жыл бұрын

+Steve Rob that would be nice to have!

@Fireship1 8 жыл бұрын

+donyboy73 you can make one with common materials such as a paint can, a tiki torch wick and some nichrome wire. Google it and or look on eBay for completed ones and kits to make your own. Not expensive at all, work just as good!

@danielh4995 5 жыл бұрын

Man I am glad I read this comment! I hadnt thought of doing that to test for leaks but I will now. I actually have an 038 Mag II that wont idle after a port, polish, and refresh. I suspect the cylinder to crankcase seal is the issue but that will be a great way to confirm.

@da8ish1 3 жыл бұрын

great video! thanks. 6:10 in i think that vacuum may be in inches

@gilbertvelazquez1254 8 жыл бұрын

Thank You Dony like all your videos

@donyboy73 8 жыл бұрын

+Gil Velazquez thanks Gil!

@snort455 5 ай бұрын

gracias

@musketbal 7 жыл бұрын

It was impossible to find anything similar to what Donny uses for the pressure test. What I did was take a large bottle cork (from hardware store) so it fit snug in the bellow with approximately 1/2" of the cork exposed . I then drilled a hole in the cork after the fit check and placed a piece of fuel line through the cork leaving enough exposed to allow for the vacuum pump to be attached. I also covered the top and area around the fuel line with black permatex RTV for a good seal. The bottom was also done in the same fashion. I then used a small hose clamp to keep it secure when installed into the bellow. Not too fancy, but if you can't find the adapter Donny uses, I think this should work.

@yveskc1 8 жыл бұрын

Thanks for sharing!

@xxMacDaddy84xx 8 жыл бұрын

What's the part number for the Stihl adapter with hose connector that you plugged the bellows with? Thanks

@davidschliebe246 4 ай бұрын

Don I just vac-press tested a stihl ms390. It's got great pressure test results. HOWEVER it won't pass the vacuum test. What could cause this result.???

@ButchElrod 6 жыл бұрын

I'm interested in that adapter, or an idea for a home made adapter, to connect the pump to the bellows.

@shawnmrfixitlee6478 8 жыл бұрын

Great vid Don , Thanks !!

@VIheavyequipment 8 жыл бұрын

hi there iv beening working on a husky 266 i can not get it to start iv replaced fuel line and filter and it has spark was running a year ago what should i do? wont fire at all even with a little fuel put in carb

@johnkosheluk1041 4 жыл бұрын

I am a stihl tech I have the same vac tester I made a tool to keep the case at 8 psi ot can be a pain to keep pumping the tester

@GHULAMABBAS-bs4hy 3 жыл бұрын

Please make the video of MS 382 chain saw trouble shooting

@miguelcicora6861 Жыл бұрын

I hook my compression tester on 2 different chainsaws 1 working and the other one doesn't both have the same reading 30psi. Any thoughts 💭.

@Norwaywildlife 6 жыл бұрын

I like this very good instruction and cool you go that deep as here on the machine repair. Thak you allot ! Keep up the good work. Very helpful for us that has a passion about making small engines run as they are intended to do. I just like to restore them...just for fun.

@patrickrusca5950 8 жыл бұрын

thanks for doing this video. very clear and helpful. all the best :)

@jayhiz3514 6 жыл бұрын

Thanks agin great video.

@nickdonato4488 8 жыл бұрын

My small engine has a problem I start it and then after like a couple seconds it dies can u make a video on how to fix it

@__oK__ 4 жыл бұрын

I think I'll have test my 3 STIHL 010 AV because they all have same symptoms.

@warrenscott9990 8 жыл бұрын

thanks Don! nice job

@donyboy73 8 жыл бұрын

+Warren Scott thanks

@friendshipyu 8 жыл бұрын

thorough advice

@shakirratheriok1857 3 жыл бұрын

Sir what happens if chainsaw leaks it bogs down under load....thanks this is most important issue in chanies saws..

@mcmaster22 8 жыл бұрын

Another Great video as always. Thanks again Dony for sharing with us.

@donyboy73 8 жыл бұрын

+mcmaster22 you're welcome, have a good weekend

@coolbluelights 8 жыл бұрын

Crank seals are very important in a 2 stroke

@geojor 8 жыл бұрын

good one, dony...

@pyrog.c.c89 4 жыл бұрын

How do you take out the seal.

@leec12 8 жыл бұрын

Excellent presentation. Timely because I just bought a Mityvac to test my saws that I work on.

@hollissmith5467 7 жыл бұрын

where can i find crank seals for a 28 boss

@phillipkramer6638 7 жыл бұрын

Pressure I was told almost always is the head gasket when its set up like you had it. Didn't know that. Thanks as always. Your videos are the best and well worth subscribing.

@jamesmullins3219 8 жыл бұрын

excellent video. Removing the seal employs a knowledgeable mechanics trick... you may consider adding that to your next version of this clop. Great editing. Thanks Dony for another good video

@donyboy73 8 жыл бұрын

+James Mullins thanks, yes I will make a seal removal video

@Chris-Fennimore 8 жыл бұрын

Good video Don. I got a couple 028s that I replaced crank seals on, but still got a leak somewhere. I'll try the pressure test on them.

@travischandler272 8 жыл бұрын

did you replace the seal with out splitting the case ?

@donyboy73 8 жыл бұрын

+travis chandler yes I just popped it out from the surface

@Fireship1 8 жыл бұрын

Great video. I wonder if this would work on a two stroke outboard. I'm guessing it would.

@Wjones450 7 жыл бұрын

I have used this way of pressure/vac testing for a few years now and it does indeed work very well. like he said tho just make sure your connections to the pump are solid! Also works great for carburetor work

@colin8532 8 жыл бұрын

Excellent video, I didn't know any of this. Thank you very much :)

@patrickrusca5950 8 жыл бұрын

hey Colin. how's life?! hope u are well.

@TedSailAwayCost Жыл бұрын

Thank you very much Donny , I believe you are the best instructor on small engines . I firmly believe you will be a great teacher in a technical training school in the future . Once again you have solved my chain saw problems and now running like clockwork . Kind regards Ted , west Australia

@gtb4 Жыл бұрын

One of the best channels I’ve seen. Thank you!😊

@MrSparkums 7 жыл бұрын

I have an 038 magnum Ii. I did the same but blocked from behind the carb covering the impulse line. Holds 6psi for over 5 min at bdc, both vac and press, but compression test from the spark plug leaks out, wont hold compression when cranking. what am I doing wrong? Great vids thanks!

@MrSparkums 7 жыл бұрын

No scoring on the cylinder, and it does run. Im thinking its piston rings.. meh!

@toddc4d 5 жыл бұрын

@@MrSparkums did you ever figure out what was causing low compression, I have no scoring and changed rings and still low compression, thanks todd

@MrSparkums 5 жыл бұрын

@@toddc4d MI It wound up being the rings.. I would invest in a mighty vac, and make some block off plates. No way to eliminate Gasket or seal leaks without a p/v test.. I wound up selling it for a pretty penny.. Instant regret...

@abigailgabriel2348 8 жыл бұрын

Hey Donny I don't know how to ask you a question but I'll ask here trying to get a respond. I just started my generator last snow storm and it was very loud and sparks were coming out of the exhaust. It's about a 10 year old generator maybe older. Need some advice

@eddiewilson4291 8 жыл бұрын

+abigail gabriel I recently watched one of Donny's videos that showed the same thing on an engine. The exhaust valve was stuck, or out of adjustment. Look for this video and I think it will help.

@douglas747wct 2 жыл бұрын

Hi, great video. I have a MS361 and the same adaptor you used for the leak down test. What did you fabricate to use it with the handle/gas tank assy removed? It makes the procedure a lot simpler! Thanks

@wtbm123 8 жыл бұрын

Good video

@donyboy73 8 жыл бұрын

+wtbm123 thanks

@lauraw3923 7 жыл бұрын

Why do the oil seals go bad? Could it be linked to overheating, lean running or dirt ingestion?

@donyboy73 7 жыл бұрын

wear and tear and if a bearing is worn it also causes the seal to wear as well thus causing an air leak

@hotbikerguy1988 3 жыл бұрын

If I had an air leak like that one would it run my saw too lean to make it overheat? I’ve gone through 2 top ends now on my Stihl ms 440 and I don’t know why!!!!!! I haven’t checked the crankshaft seals yet

@donyboy73 3 жыл бұрын

yes it would, on the 440 check the intake boot, it might be cracked

@johnkosheluk1041 4 жыл бұрын

Plus you have to be careful when you put the pump down it doesn't relice the presher the lever is on the bottom I think bad ida of the miti

@alejandrovier2958 Жыл бұрын

This pump can be used in carburetors?

@donyboy73 Жыл бұрын

Yes

@kencourtright3636 8 жыл бұрын

AWSOME informative video !

@geneballay9590 8 жыл бұрын

Very nice video

@donyboy73 8 жыл бұрын

+Gene Ballay thanks

@Ducktruckful 6 жыл бұрын

Don I was wandering after you run this test,if you can do a upper cyl leak down test with piston up to see if rings are bad, like on a 4 stroke.... thanks again great job

@davidthorne6796 8 жыл бұрын

Sweet drill out and pick grip and rip on that seal !!!! That's a sweet time saver, Sir! Thanks again

@rickforsty9410 3 жыл бұрын

Very informative!!

@hiphopman72 2 жыл бұрын

Solid video thanks

@phillipkramer6638 7 жыл бұрын

Can I use that attacher with the carb on and test the carb at the same time as long as I keep the pressure lower. Thanks for you videos which so far are the best ive seen quality.

@jjparody8257 8 жыл бұрын

During a test, I always seem to get a little air escaping from the spark plug hole even though I tighten the plug down snug. I just don't think that the metal washer on a plug creates an air tight seal. Have you experienced this, Don?

@victorboucher675 Жыл бұрын

Grease.

@JasonJFlippingLife 8 жыл бұрын

@donyboy73 I have a Husqavarna 353 that is leaking gas at the bottom tank seam. Can this cause the saw to run ragged and can it be repaired?

@davidthorne6796 8 жыл бұрын

Just need to replace the seal

@barryreynolds3801 7 жыл бұрын

yes

@mikecarey4354 6 жыл бұрын

Jason Johnston very good

@genehensley767 8 жыл бұрын

good video. Don been waiting for that one for a long time how did you remove the seals that would be my only question thanks a lot

@donyboy73 8 жыл бұрын

+gene hensley I used a sharp pic and hammer

@newyota1 7 жыл бұрын

Should the piston be at bottom or top dead center

@willywgb 6 жыл бұрын

It doesn't matter the position of the piston.

@lightshine6044 4 жыл бұрын

If a person install oil seal incorrectly on PTO side of MS660, say spring fell off inside seal, will vacuum test spot that seal? Thanks

@donyboy73 4 жыл бұрын

yes it will

@lightshine6044 4 жыл бұрын

@@donyboy73 Thanks a million. What I meant was that seal looks fine from outside appearance but spring fell off inside seal.

@stoolie10 8 жыл бұрын

you need the stihl seal tool for the flywheel side. to easy to damage the crank,etc... just saying.

@mikebones322 8 жыл бұрын

Is that just one of those brake fluid pumps???

@almo19 3 жыл бұрын

Amazing video, thank you Dony! Your videos are sooo helpful! I have a Stihl BG55 blower that I want to leak down test. Do you know how I could do that without a bellows? Is there some kind of adapter I can use to add pressure or vacuum through the spark plug hole. Thank you!!!!

@sglas7102 2 жыл бұрын

Last comment, so true. Your explanations and step by step are spot on! Bravo

@stanwilson7566 8 жыл бұрын

Could you show how to replacing the seal?

@willywgb 6 жыл бұрын

How to Replace a Seal. Using a set of calipers, measure the deepth of the old seal. Carefully drill a small hole in the side of the seal centered between the ID and OD. Install a self tapping screw into this hole. Be very careful not to drill or install the screw to deep or you will damage the crankshaft bearing. Using either a slide hammer or channel locks, grab the head of the screw and pull the seal out. Be very careful not to damage the running surface of the crankshaft or the seal bore. Clean everything up and install the new seal with the appropriate seal driver or a deep socket. Make sure to install the new seal to the same deepth as the old one. A little oil on the crankshaft surface and a light smear of silicon in the seal bore. Make sure to preform a second pressure/vacuum test. It's a good idea to give the crankshaft a turn when pressure testing older seals.

@michaeld6779 8 жыл бұрын

looking for parts for husqvarna 240 2012-2013 chainsaw. parts needed complete clutch, hub etc. saw is not 'grabbing' under load. Are you willing to get these parts (OEM) and ship. thnx

@donyboy73 8 жыл бұрын

+Michael Dobbin hi, i'm not a Husqvarna dealer, check locally for a dealer

@michaeld6779 8 жыл бұрын

+donyboy73 I don't have a local dealer. Ok Thnx.

@tonyaiello6463 3 жыл бұрын

I just love your videos!

@ice25781 8 жыл бұрын

tHANKS Dony. One more inlightful vid. Great work. Have a nice day.

@donyboy73 8 жыл бұрын

+ice25781 thanks

@RG-wy1ol 2 жыл бұрын

Thanks man for making this video very helpful 👍🏽

@willf5768 3 жыл бұрын

Great video thanks for sharing 🙂👍

@lfts2010 2 жыл бұрын

Dude! Fantastic informative video! Thank you

@jwanthuis 8 жыл бұрын

How do you "Donyboy73" replace the crank seal.

@LLStacheLarry 8 жыл бұрын

+jwanthuis I would like to see that also.

@RussellBooth1977 6 жыл бұрын

I did with an air compressor with a Stihl hedge trimmer I rebuilt, one crank seal leaked but I went to the bearing shop & bought 2 of the same sized seals for $15 AUD. The machine had other problems as well but it had no more leaks after that.

@madlybackwards5611 4 жыл бұрын

So might this seal cause the saw to leak oil from the bottom. Or would there be a seal for the chain oiler?? Thanks awesome helpful vids i cant afford to keep throwing away tools!

@RG-wy1ol 2 жыл бұрын

Thanks for making this video did you make your own parts to to the pressure test?

@leehotspur9679 3 жыл бұрын

Well presented Donny Thanks for sharing Cheers from NZ

@donyboy73 3 жыл бұрын

Glad you enjoyed it

@BrucesShop 7 жыл бұрын

I just referred a sub to you regarding crank seals. (to watch this video).

@donyboy73 7 жыл бұрын

thanks bruce

@nygardenguru 5 жыл бұрын

Does the piston have to be at TDC seems like there is a chance the piston could block the air intake and access to the bottom end of the crankcase

@jorgeortega1709 6 жыл бұрын

Another great video! Can you show us how to replace the crankshaft and/or flywheel seals on a chainsaw in the near future?

@jorgeortega1709 6 жыл бұрын

Sorry meant clutch not crankshaft

@raymondcampbell2346 8 жыл бұрын

Good info Don. where did you get your Mighty Vac leak vacum leak tester?

@donyboy73 8 жыл бұрын

+Raymond Campbell got the pump from an auto parts store, you can get it on amazon

@FixAllFixer62 8 жыл бұрын

i was just going say that

@GHULAMABBAS-bs4hy 3 жыл бұрын

Very good service Knowledge

@JoeBakerOutsideTheBox 8 жыл бұрын

would a 4 stroke horizontal Briggs be tested that way?

@zzzdogutube 8 жыл бұрын

When you draw a vacuum it is in (Inches of HG) not PSI. You misspoke. Also, what are the symptoms of a leak? Thanks.

@CarstenLorenzen12V 8 жыл бұрын

+zzzdogutube The symptoms would be a lean running engine, as it would draw more air to the gas/air mixture, past the carburettor. This could result in "bogging" when you open the throttle, fast idle rpm, overheating engine and worst case scenario - seized piston.

@zzzdogutube 8 жыл бұрын

Thanks, that what I thought.

@pbrstreetgng79 8 жыл бұрын

+zzzdogutube In addition to Carstens comment, a saw that won't idle properly, no matter HOW much you adjust the carb is another symptom. Sometimes it will rev up without even touching the throttle.

@zzzdogutube 8 жыл бұрын

pbrstreetgng79 Thanks

@mikecarey4354 6 жыл бұрын

zzzdogutube cool

@semco72057 8 жыл бұрын

That is nice to know and I didn't know about that going wrong on the saws.

@neiltaylor4019 6 жыл бұрын

Hi I watch all your videos on small engines, would it be possible to let me know how to do a pressure and vacuum test on a Stihl BR600 Leaf Blower. As I can’t find any videos on this. Thanks and regards Neil Taylor.

@jbbolts 2 жыл бұрын

hey would that tester work on carbs as well? thanks really appreciate your videos

@lewishodge4935 3 жыл бұрын

Dony: I'm waiting on my order of a MityVac vac/pressure gauge to test my saws. I'm wondering if this would make things easier? I propose using a rubber stopper in the intake boot. It might have to be held in place under pressure, but may work very well under vacuum. Then perform test through the impulse line. What do you think?