Pressure Test

[WaveDemon]

ive used the expanding plugs before, but the easiest method i have found is rubber gasket material. cut 2 pieces. one goes between the carb and manifold and the other goes between the headpipe and manifold. only cut the bolt holes and not the bores and bolt your carb(s) and pipe. dont go past 8 lbs psi.

if you only have one pulse fitting, just put the guage on a tee between the air pump and pulse fitting.

you shouldnt see ANY droppage in pressure. if you do, pour some soapy water onto the engine and look for the bubbles.

make sure to do the test w/ the flywheel cover off.

ditto

 

[Yamah0]

no need to remove the flywheel.....hopefully.

youre removing the cover so it doesnt hold pressure and give you a false reading if your front crank seal is bad.

Hmm... Thank you Boss!:biggrin:

 

[Metal4130]

This is a dumb question, once you find the leak what do you do next? RTV silicone or something like that? seal the gaskets? If you want I will take pictures of the plates and guage that I made for my gp1200 engine.

 

[ski4]

with all the money wrapped up in this rebuild and new crank etc, i would have to say i would be pulling apart the motor again and making sure the mating surfaces are good and put it back together, don't need no free revin' mess blowing up on me

 

[ski4]

well, put her all together, and plugged her up
took it to 6 lbs ( negative pressure cuz i have a vacuum guage) and she held:cheer: it all for 10 minutes.


wooo hooooooooooo:biggrin: :biggrin: :biggrin: :arms:

 

[MADMAT]

Sweet!!! Things are looking up!

 

[ski4]

hell yeah
carbs are rejetted, finally got the pigments i needed for the paint from the local paint shop ( finish masters) they were so incredibly cool. and also told me i got robbed blind on the paint i bought which i was a little disheartened to hear
still waiting on some people and parts
m &m and jss come on guys get back to me

then i can throw it all together,
could be ready to ride next week ?????????

 

[djkorn1]

shooooooooooot. When I get back from Tahoe.. my mission in life is to finish my ski! Hopefully I will be able to ride before Lanier...

 

[ski4]

Dude get out on the slopes, wht the hell you doing surfing the net.
squaw awaits brotha
go do broken arrow for me and mosely's run

 

[swapmeet]

Bump this up.

I'm trying to do a pressure test to on my motor and I want to make sure this looks right.

I made block off plates out of 3/16" aluminum plate for the exhaust manifold where it attaches to the B-pipe.
Made another one for the carb hole on the intake. I used 9mil underpad to seal the holes, cranked the bolts down pretty snug to ensure a seal.

I took a bike pump that has a inline gauge that shows pressure as its applied. I pulled the bike fitting off and ran the rubber hose down on the pulse fitting on the intake.
I hose clamped it and gave it a few slow pumps. After 3-4 pumps nothing was registering on the gauge. I backed the nuts off the carb block off hole and there was pressure built up in the intake (???). So now i'm confused, did I not pump it up enough? Should I have kept going? I didn't want to damage any seals by applying too much pressure.

Here's a photo, let me know if this looks right.

 

[Proformance1]

Im no expert but you may damage the reeds if you apply too much pressure this way, if your reeds are sealing perfectly. You are creating a back pressure on the reeds. From what I have read, you can do it this way but be careful to use low enough pressure not to damage reeds.
On your question if the bike pumps gauge is low enough you should have just kept pumping

 

[swapmeet]

I was pumping VERY slowly for that reason. But since nothing registered I was concerned that I was building pressure and damaging something and not knowing about it. I may try to get a gauge with a lower range today. This one tops out at like 250psi (road bikes) but I assumed that 5 psi would show.

One member said they remove the reeds to do the test, but that didn't make sense to me because then you're compromising the gaskets that you're trying to test.

So just pump away eh?

 

[hornedogg79]

I don't think their could have been enough pressure to show on the gauge at just 3-4 pumps. It likely wasn't enough psi to read on gauge. I have a pretty nice pump and it doesn't really start reading until about 10psi. Use a gauge with a smaller range if you want to be safe. Like 0-35psi.

 

[XJCrawler]

Bump this up.

I'm trying to do a pressure test to on my motor and I want to make sure this looks right.

I made block off plates out of 3/16" aluminum plate for the exhaust manifold where it attaches to the B-pipe.
Made another one for the carb hole on the intake. I used 9mil underpad to seal the holes, cranked the bolts down pretty snug to ensure a seal.

I took a bike pump that has a inline gauge that shows pressure as its applied. I pulled the bike fitting off and ran the rubber hose down on the pulse fitting on the intake.
I hose clamped it and gave it a few slow pumps. After 3-4 pumps nothing was registering on the gauge. I backed the nuts off the carb block off hole and there was pressure built up in the intake (???). So now i'm confused, did I not pump it up enough? Should I have kept going? I didn't want to damage any seals by applying too much pressure.

Here's a photo, let me know if this looks right.

You cant go by the gauge on the pump, you need to tap your plate on the intake and add a fitting so you can attach a proper gauge

 

[swapmeet]

Ok, will do... Thanks ya'll!!!!!!!!!!!!!

 

[WaveDemon]

I bought my pressure tester from watcon. it's a bike pump with an inline gauge, also the kit had a few pieces of rubber that went under the carb and under the exhaust manifold. hook up the pump to the pulse fitting and pump it up to 8-10psi and make sure it holds for ~ 5 min.

 

[Proformance1]

FYI, Here was a thread on the pressure test kits I made a while back. You'll see the part about the pump and also drilling the hole in the carb plate and testing at 5 psi or less for a reed test.

http://www.x-h2o.com/threads/73235-62T-61X-Pressure-test-block-off-kits-For-Sale&highlight=

 

[Pablo]

Waternut made a nice setup that I'm about to use. I think he used a MTb shock pump that uses a real easy to read pump gauge.

 

[swapmeet]

I really appreciate the feed back everyone is giving me. I'm taking it all in I promise.

Proformance1, on the pic you sent it looks like pulse line port was on the case, not the intake manifold.

Am I correct to be pressurizing from via the pulse port on my 61X or should I add a port to the carb plate? I didn't think it mattered but I wanted to ask.

 

[Proformance1]

IMO it matters especially if you go over 5 psi. which I have been recomended to go to 7 or 8. You are pressurizing the back side of the reeds. Think of the reeds as plastic wrap or a balloon. you are only pumping on one side of the reeds and sealing the other side off, if they seal "perfectly" they "could" crack. Im my pict there are no reeds installed, no intake either.