Propane ?

76nick · Aug 27, 2013

How much vacuum is needed to run propane..I was told it wouldn't run right if not enough vacuum was produced.. Reason I'm asking is because I can get my hands on a pretty healthy motor but owner said he didn't think it made a lot of vacuum because brakes were never very good once he put this motor in his truck. Any help it knowledge would be greatly appreciated

Rockwells607 · Aug 27, 2013

My motor produces very little vacuum in my buggy, I have to push the primer/purge button to start it most of the time and then it fires up and runs fine, my jeep had. Mild cam and makes vacuum , just push starter button and it fires right up and runs fine

76nick · Aug 28, 2013

Anybody else?

bigjerm · Aug 28, 2013

Re: Re: Propane ?

I have propane on the 22re in my yota buggy. I know the vacuum line between the engine and booster is leaking. The engine idles better when I pump up the brakes and hold. Didn't discover the really bad brakes till ledge of faith at GAP

Sent from S3

Fire Freak · Aug 28, 2013

I have a healthy 383 with two mixers love it

BUG-E J · Aug 29, 2013

A single mixer is only gonna make 350-400 horses MAX. Don't waste your money on a big cam that wont allow enough vacum to start the engine.

bigredkacy · Aug 29, 2013

Rockwells607 said:
My motor produces very little vacuum in my buggy, I have to push the primer/purge button to start it most of the time and then it fires up and runs fine, my jeep had. Mild cam and makes vacuum , just push starter button and it fires right up and runs fine

I am with him
I am running a 521 stroker on propane. I have very little propane. The only reason why it requires propane is for the lockoff. It needs to build up to open the diaphragm up.
Once i get it started ( 30 seconds of cranking and 1 primer push ) it runs the rest of the day without problem.
You can change the lockoff to a electric lockoff and be good.

Paperstreet10 · Sep 3, 2013

Not trying to jack the thread, just don't see a point in starting a new one. I just got a rig that has propane conversion. The 22r runs fine... When it wants to. It has just flat out died on me three times randomly while driving. The third time I couldn't start it back up. Plenty of pane in the tank but it seems the engine is not getting fuel. Any advice? This is my first truck with this setup so I'm not very familiar with troubleshooting.

TBItoy · Sep 3, 2013

Paperstreet10 said:
Not trying to jack the thread, just don't see a point in starting a new one. I just got a rig that has propane conversion. The 22r runs fine... When it wants to. It has just flat out died on me three times randomly while driving. The third time I couldn't start it back up. Plenty of pane in the tank but it seems the engine is not getting fuel. Any advice? This is my first truck with this setup so I'm not very familiar with troubleshooting.

is the evaporator freezing up?

problems with one tank or multiple tanks?

Paperstreet10 · Sep 3, 2013

TBItoy said:
is the evaporator freezing up?

problems with one tank or multiple tanks?

No freezing from what I could tell earlier, and I have two vertically mounted tanks that I've tried swapping to and from with the same issue either way. A buddy of mine seems to think it could be the mixer. I'm not very familiar with propane so this is a learning experience for me to say the least

Pumpkin · Sep 3, 2013

Buddy should be seeing this post when he gets online. He is the propane guru.
http://www.hardlinecrawlers.com/forums/index.php?action=profile;u=1211

al1tonyota · Sep 3, 2013

bigredkacy said:
I am with him
I am running a 521 stroker on propane. I have very little propane. The only reason why it requires propane is for the lockoff. It needs to build up to open the diaphragm up.
Once i get it started ( 30 seconds of cranking and 1 primer push ) it runs the rest of the day without problem.
You can change the lockoff to a electric lockoff and be good.

This is not right! It takes vacum to pull the mixer open so that propane comes out by pressing the purge you are essentially dumping some propane in to start the engine thus creating more vacum so it stays running!

Rockwells607 · Sep 3, 2013

I hafta purge mine every start unless its only been off a matter of seconds , purging it pushes fuel into motor when it's
Makin little to no vaccum not running, after it fires it must
Make alittle or enough cuz it runs fine

al1tonyota · Sep 3, 2013

Rockwells607 said:
I hafta purge mine every start unless its only been off a matter of seconds , purging it pushes fuel into motor when it's
Makin little to no vaccum not running, after it fires it must
Make alittle or enough cuz it runs fine

Hook a vacum gauge to it and see what you got at crank and at idle?

billstoy · Sep 3, 2013

all of you with low vacume I know a turbo rig that uses a nitrous purge solanoid for a push botton release of propane to motor for dry starting. it was a good idea and everyone sees the soloniod thinks he has NOS quick push of the botton quick fireup .

bigredkacy · Sep 3, 2013

billstoy said:
all of you with low vacume I know a turbo rig that uses a nitrous purge solanoid for a push botton release of propane to motor for dry starting. it was a good idea and everyone sees the soloniod thinks he has NOS quick push of the botton quick fireup .

Haave any more info on this?

Rockwells607 · Sep 3, 2013

It's not really a deal breaker for me, sometimes seems anoying but the motor runs great, with that being said, the new buggy I'm building for my wife will have propane and I will pick a milder cam better suited for propane so she won't hafta fiddle with it

tbacon38 · Sep 3, 2013

I have to prime mine after it has been sitting for a while, after it warms up it starts no problem unless it sits for an hour or so. im running a big solid cam in mine and seems to do pretty good, it may lose fuel if I hold it wot for a long time and high rpms but other than that it does pretty good, I have 2 impco 425s on mine, everyone always told me a single 425 was good for 300 to 350 hp.

altfuel1991 · Sep 3, 2013

Paperstreet10 said:
Not trying to jack the thread, just don't see a point in starting a new one. I just got a rig that has propane conversion. The 22r runs fine... When it wants to. It has just flat out died on me three times randomly while driving. The third time I couldn't start it back up. Plenty of pane in the tank but it seems the engine is not getting fuel. Any advice? This is my first truck with this setup so I'm not very familiar with troubleshooting.

You didn't say how old the system is in your rig or how long since a good tune up. Are you sure it is a fuel problem and not a spark problem? The thing about propane is that the systems are dirt simple. If you have a vacuum signal at the mixer it will draw fuel from the vaporizer. Spin the engine over with the air filter off and watch the air valve. It should pulse up and down when the engine is spinning over. If you have a good spark at the plugs, there might be a problem with the vaporizer. Usually it will flood the engine when it needs to be rebuilt. Can you tell me what components are on your engine? If Impco, which mixer, vaporizer and lockoff valve? We see very little trouble with mixers unless there have been multiple back fires through it. Check your vapor hose between the mixer and vaporizer for cracks. Does it smell rich when running? Sometimes a flooded engine acts just like an engine getting no fuel. You can put a pressure gauge on the vaporizer and check for proper pressure at the test port.

Also, Kacy, glad to see you got the stroker installed. Give me a call and let me know how it is running. You should be able to use all the dual mixer setup has to offer.

Paperstreet10 · Sep 3, 2013

altfuel1991 said:
You didn't say how old the system is in your rig or how long since a good tune up. Are you sure it is a fuel problem and not a spark problem? The thing about propane is that the systems are dirt simple. If you have a vacuum signal at the mixer it will draw fuel from the vaporizer. Spin the engine over with the air filter off and watch the air valve. It should pulse up and down when the engine is spinning over. If you have a good spark at the plugs, there might be a problem with the vaporizer. Usually it will flood the engine when it needs to be rebuilt. Can you tell me what components are on your engine? If Impco, which mixer, vaporizer and lockoff valve? We see very little trouble with mixers unless there have been multiple back fires through it. Check your vapor hose between the mixer and vaporizer for cracks. Does it smell rich when running? Sometimes a flooded engine acts just like an engine getting no fuel. You can put a pressure gauge on the vaporizer and check for proper pressure at the test port.

Also, Kacy, glad to see you got the stroker installed. Give me a call and let me know how it is running. You should be able to use all the dual mixer setup has to offer.

It is an impco, ill have to get back to you on the numbers. The first two times it cut off, I was actually driving down the road running great. Both times I let the truck sit for about 20 minutes and it cranked right back up and drove home. Not sure on age of the system. Ive only owned the thing since Saturday. What's an avg lifespan of a vaporizer?