Chemical Shelter engine

[wreckerman893]

While I was resting and celebrating Robert E. Lee's birthday on Monday I decided to see if the engine that powers the Chemical Shelter trailer would fire off.
Myself and Freight Train had made a successful parts run to Double Deuce's place near Montgomery on Sat. I scored an original 24 volt battery that fit in the battery holder on the trailer. I added acid to the battery and made sure it had a full charge.
I got the battery mounted, made sure the engine turned freely, and sprayed some Marvel Mystery Oil into the cylinders.
Since I didn't trust the original fuel tank not to leak I rigged a temporary one using a lawn mower tank. I had freed up the frozen throttle linkage and bypassed the old fuel line and an electric fuel pump that also sent fuel to the multifuel heater mounted on the trailer.
When I gravity fed the fuel into the engine fuel flowed out of an orifice just in front of the choke butterfly.
I had my son push the start button a few times but it never fired off.
I then put the tank lower that the carb to keep the raw fuel from coming out of the choke and I wasn't sure the fuel was going to the carb. A few more tries and then I gave up to keep from draining the battery.
This is the Hurcules 4 cylinder, air cooled, 85 CI engine that was used on a lot of military equipment to include air compressors, generators and maybe the Mule.
Does anybody have any experience working on these engines???
What size spark plug wrench pulls the plugs?
If this engine runs I may can recoup a large portion of my investment in this trailer.
Any help would be appreciated.

 

[Recovry4x4]

I would look towards crap on the points inide the magneto. Every single 4A084 engine I've ever had with a no start symptom required cleaning the points. Once you clean the points, they don't stay clean very long so then new points are in order. I would try cranking it with some starting fluid just to see if you get a kick. Also has a low oil shutdown so check that too. Might initially jump it over to see if you have some spark. Have you downloaded the engine manuals yet? They are available here.

 

[wreckerman893]

Thanks 4x4.
I am working on this during my (intermitable) wait for my next assignment.
I'll go out and get the exact model no. off of it and try to download the manual.
I thought about the starting fluid but I was worried that using it on a gas burner might result in damage.
Still need to know the spark plug wrench size if anyone knows.

 

[Recovry4x4]

TM 9-2805-259-14 is the engine TM

 

[littlebob]

Having worked on many small engines, It sounds like you have a stuck float, or a leaking needle and seat on the carbs.Pull the plugs and check for wet plugs. If wet the engine is probably flooded and the cylinders could have unburnt fuel in them. Like recovery said, the first thing to check would be spark and then diagnose from there. Don't remove the plugs and check for spark with the cylinders open and possibly full of fuel, BAD things could happen if you try and check spark and the cylinders are full of fuel. Check the spark with a known good plug out of someting else with all of the plugs still in. If you get a spark with a good plug then the ignition is doing its job. Not being famillar with those engines yet, the next step would be to is to cut off the fuel supply and remove all plugs, then
ground the coils to allow you turn it over with out making a spark to purge any unburnt fuel from the cylinders. What I've done ine the past just to get something to fire off is just let enough fuel into the carb to run it for a few seconds(before the fuel comes out somewhere), then try to crank it with known good plugs.
The plugs can be beed blasted or heated to glowing with a torch to remove fouling just to try and get to fire. I wouldn't suggest doing this for regular use.
If you have afire extinguisher I would keep handy for any of this.
Good Luck,
littlebob
P.S. Did you get my PM's

 

[OPCOM]

Hope you get it running, I like small engines.

 

[peyton]

Having worked on many small engines, It sounds like you have a stuck float, or a leaking needle and seat on the carbs.

I have had continuing problems with sticking float in my 4a032. The fuel causes the float to swell and then it sticks (both open and closed) against the side of the float bowl. Good luck.

Peyton

 

[Crazyguyla]

Spark plug wrench 7/8

 

[wreckerman893]

Many thanks for the replies. I tried the ether tonight and it didn't fire. That leaves the electrical issues. This thing has several systems on it and anyone of them could have a override switch that would keep the engine from starting. I made sure the oil level was good before I tried to fire it off.
Tomorrow I will try to access the points and give them a cleaning.
I have tried several times to downlaod the manual but for some reason my dial up won't let me do it.

 

[ida34]

While I messed around with my 10k I could not get it to fire. It was getting spark and the plugs were new. I cleaned the carb and it still would not work. Even either would not help. I have not had a chance to get back to it but I was able to see that the fuel pump was working. I have not tried my other 10k yet. Who knows when I will have time. I am really kind of stumped. It has compression and it is getting spark. The either should have offset any fuel problem. It did not want to crank over real well so I am thinking maybe the engine is tight for some reason. It seemed to take a pretty good pull with the rope to get it to turn over. I have to check the other engine to see if it is tight also. Be sure to post what you find out.

 

[mangus580]

Oh yeah... another thing worth checking... Timing, and firing order! (when you take the mag out, be sure to tag the wires.... Otherwise you have to call someone for help! Thanks Bjorn!!!)

 

[ida34]

Will an inductive timing light work through the sealed wires? I need to check the firing order also but I don't get any backfire or weird cranking that is usually associated with a wrong firing order situation. I will compare my two engines when I get a chance and check them out with the TM on the firing order.

 

[wreckerman893]

I cleaned the points as per above instructions and also the plugs.
I gave her a small shot of ether and put the fuel to her.
She fired up but hit wide open throttle and I cut it off.
Now that I know it will run I can address the fuel issue and see if it needs an electrical pump or if it will pull fuel to it.
Thanks to all that helped.

 

[Recovry4x4]

FWIW WOT is good. Guess we forgot to mention this one little point. These gensets have a problem with regulators. Seems that if the engine is allowed to idle, the regulator cooks. I wouldn't let it idle more than a few seconds myself. Chuck, the inductive light will not work on these wires. I've heard of people using a regular wire and plug on #1 so that they could time it. There also exists a electrical adapter kit for this purpose. I have a surplus timing light kit that has the adapter and runs off 24v

 

[mangus580]

These gensets have a problem with regulators. Seems that if the engine is allowed to idle, the regulator cooks. I wouldn't let it idle more than a few seconds myself.

Funny thing about this is.... I think the manual states to idle it down? (or CRS has got me again...)



On the timing thing, Get a piece of plugwire from an old tractor, with no ends on it. strip back some wire on both ends, fold it over, and shove it in the plug an the dist cap. This should give you good enough connection to run it and use a timing light. (you might have to build up diameter a little to get it stay.)

 

[Recovry4x4]

Mike, I think the engine manual does say that. The genset manual says this;

 

[mangus580]

LOL the 'NOTE' cracks me up.... If the battery wasnt weak, why the #$% would I want to pull start one of them beasts????

 

[Recovry4x4]

If anyone wants to crank one, go ahead! I'll slave it or it won't be started. I've had my fill of them ropes.

 

[mangus580]

"Wrap & Hope"

just found that funny... if the battery is good, then just use it!

 

[wreckerman893]

Recovery......thanks for the excerpt from the manual. I still can't get the ^%*&^ thing to download.
The truth is indeed stranger than fiction.