problem with a prochem blazer

[brendan]

hey there,,wondering can anyone help,,,prochem blazer starts up fine then give it some throttle and block vacuum slot seems to put strain on engine and it cuts out,,,took air filter off same thing,,no oil coming from the head so dont think its the head gasket,,head scrather,,id be grateful for any ideas,,thanks

 

[renegade_cowboy]

hey there,,wondering can anyone help,,,prochem blazer starts up fine then give it some throttle and block vacuum slot seems to put strain on engine and it cuts out,,,took air filter off same thing,,no oil coming from the head so dont think its the head gasket,,head scrather,,id be grateful for any ideas,,thanks

Did you check your vac relief valve?

 

[brendan]

hey bruce lee,,yes when i press on the relieve valve the engine starts running normal

 

[renegade_cowboy]

hey bruce lee,,yes when i press on the relieve valve the engine starts running normal

Do you think the valve might be too tight? Sounds like the engine runs fine, just not under heavy load. Try looseing it.

 

[brendan]

yeah thanks ill try that,,would it tighten up threw use,,,

 

[renegade_cowboy]

yeah thanks ill try that,,would it tighten up threw use,,,

Not sure, check for lint buildup around it. When you say you close up the vac port, do you block it off completely? so no air can get iin the tank?

 

[brendan]

yes just but my hand over vac slot engine stats struggling and cuts out,,same when i put wand to the floor,,,im getting suction just engine dies

 

[renegade_cowboy]

yes just but my hand over vac slot engine stats struggling and cuts out,,same when i put wand to the floor,,,im getting suction just engine dies

I would put money on it that your valve is to tight. Its not allowing air inside the tank when you block off the vac port.

 

[renegade_cowboy]

Either that or you engine is going to need some serious work.

 

[SMRBAP]

I believe your relief valve should be set to open at 14" if I am remembering correctly, check your manual.

If that is set properly, could be a weak pulse fuel pump.

It's a $40 part from any local briggs repair shop and takes 3 minutes to do.

 

[brendan]

haven had a chance to look at it today but the fuel pump did seem to be working fine,,thank for all your post,,,

 

[renegade_cowboy]

Lets hope its not a leprechaun shiteatinggrin

 

[brendan]

lol well if hes gppd at engines he can have a look

 

[packfancjh]

pull out the pre heater on the bottom right hand side right by the front panel. Check to see if there is any build up on it. Kind of sounds like a back pressure issue caused by a clogged heat exchanger.

 

[XTREME1]

The fuel pump either goes or it doesn't (it is electric) if it stops working it is the fuel pump my guess is debris in either 2 of the filters or your fuel is bad or running rich. Look at your main fiel filter and see if it has debri or just replace it if it is metal and run off of a 5 gallon tank for a while if you don't bog down it is a fuel problem if it does start looking at other things. Usualy if it is a fuel problem your spark plugs will arc out etc and fool you

 

[brendan]

thanks for all your replys,,,im taken the carb out and checking for dirt,,,if the heat exchangers where blocked would this cause the engine to run bad,,,

 

[Todd Anthony]

Yes that is what your exhaust runs threw is what they are saying. It will cause back pressure if the exhaust is not getting enough air flow because the heater core is plugged with debris.

 

[brendan]

defo not a fuel thing so that does sound visable,,had something like that before where i wasnt getting enough heat threw blocked heat exchangers,,,do i usually take them out and clean every six months,,,but it is something to look at thanks,,,either that are im going to set the thing alight

 

[packfancjh]

pull the 8 bolts off of the pre heater on the side and pull it out. I'm sure you will find the inlet side of it coated in hair and carbon. gently scrape off what you can without bending the flanges and soak it in HOT water and a good degreaser. That should take care of the problem. The more you clean it the better air flow you will get. Be prepared to replace the gasket on it though. They usually rip if they have been on there for a while.

 

[Shane T]

Start with the simple stuff first. My first guess is the ignition is breaking down somewhere, its also the easiest and least expensive to repair. Sometimes these engines will run fine even at full thottle but when you start putting it under load the ignition can fail. Make sure all primary and secondary wire connections are tight, then go to the plugs and wires. Finally check the ignition modual.

 

[packfancjh]

Did you ever find out what the problem was?

 

[brendan]

hey lee,have the blazer in with a guy to try to fix it,,,looks like its not firing right on a cylinder,,when i get it back ill let you know what was up,,,thanks

 

[The Magician]

Start with cleaning your relief valve sounds stuck closed.

 

[steve g]

my machine which is a prochem legend aka bridgepoint saber and it has an 18hp briggs motors so the same motor as your machine. my machine was backfiring and popping through the carb and not running very well, it was as if the motor was on one cylinder sometimes, other times once the machine was warmed up it ran fine. it would get really bad under load.

this sounds pretty similar to your problem, kelly mccloy at one of my suppliers suggested checking the plugs, I did they looked OK a little carbon here or there but no big deal, electrode a little burned down but nothing that looked to be a problem. they had been in for about 1000 hours though, so I decided what the heck change them out. PROBLEM CURED!!!! what I think happened is these new plugs have about a 32 thousanths gap the old ones had widened probably to nearly 50 if not more. the ignition on these little motors isn't strong enough to jump that kind of gap very well and was causing my issue. machine has not missed a beat since.

 

[brendan]

hey,,,guy now telling me that it looks like a coil is gone in the engine ,its only sparking on one cylinder,,,heres hoping,,thanks for everyones help

 

[Shane T]

Did you read my post from Feb 4?

 

[brendan]

hey shane,,yes i read your message and yes you where right,,i ran machine and disconnected one plug connection still ran,put that back on and done the same with the other and it stopped so new it was a cylinder not firing,,thanks for your info,,coil in the post

 

[XTREME1]

how did it workout?

 

[brendan]

it was a dodgy coil,,just waiting on the part,,thanks