another damn propane problem

twiztedzuki · Aug 28, 2011

vacuum lock, impco model, e and 425 impco mixer on roller 383, WOT it dies and have to reprime it! i have checked for leaks, reg is not freezing, soon as push prime on reg it fires back up? :dunno:

i have searchd everywhere cant seem to find a answer

shortcut · Aug 28, 2011

I had the same problem not long ago ..Soon as I'd go WOT it cut out immediately..Checked everything I could and was convinced it was a problem in the Msd box changed it out but didn't help at all..after many hrs. Of troubleshooting I was checking the valves on my tank when noticed the o-ring on valve looked dry rotted..Sure enough put a new o-ring on and haven't had a problem since..This probably isn't your problem but I thought I'd post it anyway .
All I can figure is the bad o-ring was letting it suck in air. :dunno:

twiztedzuki · Aug 28, 2011

i'll check that first thing tomarrow!!! it has me puzzled, but i appreciate ur help

twiztedzuki · Aug 29, 2011

all connections on lines and tank look good, ran it again, runs great untill wot then it like it starved completely of propane. is this possible?

JRH · Aug 29, 2011

bypass the lockoff and see if that is your problem

kennyWayne · Aug 29, 2011

JRH said:
bypass the lockoff and see if that is your problem

thats what i had to do to mine ,bypass lockoff . :dunno:

twiztedzuki · Aug 29, 2011

will do guys thanks for help, u guys running without lockoff or changed 2 new one?

shortcut · Aug 29, 2011

No lockoff for me ..most people don't use them

twiztedzuki · Aug 29, 2011

what ive been told by few Tn boys, i run it without and try hope it cures this pain in the ass stalling!

JRH · Aug 29, 2011

I run a lockoff on mine. VFF30 and have never had any problems. Had a friend that had a somewhat similar problem and it ended being his lockoff. I wouldnt ride all the time without the lockoff just as a safety precaution but just to see if that is your problem.

twiztedzuki · Aug 30, 2011

thanks for info guys! i took lockoff apart and diaphram was in good shape but when i took filter side apart, filter was black full of ****! cleaned and put back together, so gonna try that and if not take lockoff off and try. i let u kno how it goes

tbacon38 · Aug 31, 2011

We got 4 buggies with no lockoff and no problems so far.

twiztedzuki · Aug 31, 2011

how much more propane does it use without lockoff? dont wanna leak it out on a beer break!

twiztedzuki · Sep 5, 2011

bypassing vacuum lockoff did fix it! so now, buy new vacuum lockoff or a 12v lockoff? Thanks for help guys!!!

tbacon38 · Sep 5, 2011

twiztedzuki said:
bypassing vacuum lockoff did fix it! so now, buy new vacuum lockoff or a 12v lockoff? Thanks for help guys!!!

I wouldn't waste money on a lockout mine does not bleed off while the motor is not running.

JDean · Sep 5, 2011

Im no motor expert but my Dads roller 383 doesn't pull enough vacuum and he had to put an electric pump on his car for his brake booster. Could that be the problem at WOT?

altfuel1991 · Sep 12, 2011

I am in the propane conversion business and have been for twenty years. Our shop supplies kits and components for all types of engines and applications and we have many systems on rock crawlers. Are you running your vacuum lockoff on ported vacuum or manifold vacuum? If it is manifold vacuum that would explain why it cuts the engine off. It probably takes a few seconds to choke the engine down before it goes dead. At wide open throttle you have "0" manifold vacuum. Change your vacuum hose to a port on the mixer above the throttle blades and it should help.

There are guys not running lockoffs but it is not advisable. If the vaporizer gets a little piece of debris in the seat it can hold it open and load the motor up when not running.

If anyone needs help you can give me a call @877-403-7827 or email me [email protected].

Buddy

twiztedzuki · Sep 12, 2011

thanks i check on where vacuum is routed, so do vacuum lockoffs go bad? i cleand filter b4 i took it off and didnt help any

altfuel1991 · Sep 14, 2011

The lockoffs do need to be rebuilt occasionally. The diaphragm can get a hole in it especially if you run out of fuel and have a lean backfire. The o-ring and pin can wear and LPG will bypass and enter the engine through the vacuum hose.