# Vintage (1988) Coleman Powermate 4000 rebuild



## Ground Fault (Jun 9, 2020)

First, thanks for reading this thread. After Rita in 2005 and Ike in 2008, sometime in 2009 I took apart my Powermate 4000 with the intention of checking/replacing the brushes and capacitor. It has sat disassembled, the endbell off of it, under my workbench for 11 years. I estimated at that time that it had somewhere in the neighborhood of 800 hours on it, but could be less. Fourteen days constant after Rita in 2005 and thirteen constant after Ike in 2008, with oil changed every 50-75 hours, plug and air filter as specified. Also used it quite a bit between '88 and 2005, 3-6 hours at a time. Back then power went out quite often out here in these woods and we were not high on the priority list as there is no industry or healthcare facilities. All these years it has been under there in pieces, mocking my existence, projecting guilt upon me for not finishing it up, but I bought a Generac in 2010, so. Now I fear the dependability of the Generac, feel I am living on borrowed time, so it's time to get the Powermate going again.

Your input is valued greatly. Please take a look at the pictures of the wiring inside the endbell and identify any issues you see. I have the Reliance L14030 30amp 125/250V shore power box with recessed male TwistLock receptacle under my eave to connect either generators, it wired into my breaker box w 6ga multistrand to my breaker box, connection made using a 30amp double breaker. 

Any changes to the way the endbell should be wired?

Are the two capacitors compatible?

Doe anyone know the Torrington part number for the needle bearing in the endbell?

Notice the cracked exhaust where the exhaust pipe enters the muffler. Would you try fixing that or just go with another type of muffler for the 8hp Briggs? Which one do you recommend?

I am not real wild about putting gasoline into a 32 year old PLASTIC gas tank. Especially one located right over the source of ignition. How many heat cycles has it gone through in 32 years, how brittle is it all these years later, and how much vibration would it take to start a stress crack? So I need to come up with a better gas supply plan rather than go back with that gas tank.

And just how many hours can you put on a Briggs before you should rebuild it? It never gave me a single problem. Started on the first or second pull every time. Loudest machine ever invented.


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## Ground Fault (Jun 9, 2020)




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## Ground Fault (Jun 9, 2020)




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## iowagold (Jan 22, 2020)

well if some one is handy with a tig and stainless filler and maybe some flux they can repair the muffler...

super easy to blow through that pipe with any other welder..
it would have to be clean...

or just stick weld it with stainless rod...

bearing, any good bearing shop should be able to size that for you!!
we are lucky to have 2 of them here in town.

as far as the fuel tank... when you press on the tank does it make a cracking noise like fiber glass breaking?
if so replace the tank..

most of the time those tanks will last a long time if they are stored indoors out of the sun and no ethanol.
i bet you could use any tank on it that would fit inside the rails.
if the new tank was too small ... then adapters could be made!


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## Ground Fault (Jun 9, 2020)

Wow. Didn't expect that. Took my time freshening it up, but didn't tear the carb down as I was always careful to run it dry. Figured I'd at least try starting it before taking the time to tear the carb down. Last time it ran was September 2008, so it was iffy. A small spritz of starting fluid in the air cleaner and one pull and it cranked right up. I had put some oil in the cylinder a few weeks ago and pulled it through to distribute it around, so it smoked a little bit. Before starting noticed a slow gas leak from the tank shut-off valve: the packing seal around the valve shaft had given up the ghost. I've ordered another valve and gas tank grommet. So I had removed the gas line from the carb and the tank off the generator so as not to start a fire before starting it. It ran until the gas in the carb ran out. Still the loudest mechanical device ever assembled on this planet., but it runs! Gonna' be a great backup to my primary generator. Next, decarbon the Briggs and change the oil again. What is your preferred decarbonizing product? I'm wanting a through-carb fogging application like Yamaha's Ring-Free, but may just use Sea Foam's through-carb stuff. Anything even better?


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## Ground Fault (Jun 9, 2020)




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## iowagold (Jan 22, 2020)

the best is a head removal tear down to clean the top engine and the head...
that way you get all the trash out to perfect clean.
watch where the trash goes.
if the chamber is that bad remove the piston and clean the piston and rings too.

later model ohv engines get less trash in the head...


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## Ground Fault (Jun 9, 2020)

May have to do that anyway: You see that piece of cardboard wedged under the engine? That is its "diaper". It has a very slow oil leak, as far as I can tell from the shaft-side engine plate gasket, not the shaft seal. About a drop or two a month. Just enough to stain concrete. Been doing it for years as it sat under my workbench. If the Briggs survives the through-carb de-carbon fogging and a scope inspection of the cylinder walls reveals piston-ring gouging from carbon build-up under the ring, AND/OR the compression is low I will tear the Briggs down and rebuild it. Probably indicated anyway with shaft seals 33 years old. I'd love to find a reason to tear it down just so I could replace that side plate seal and stop that leak. It mocks my existence, but not enough to cause loss of sleep or appetite, or compel me to tear it down just for that.


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## drmerdp (Apr 10, 2018)

Those old Briggs motors typically have two issues after many hours. One, valve lash gets tight which requires removing the head to repair properly.

The second effects engines which don’t use a gravity feed fuel system. The diaphragm in the carb mounted pump gets hard.

I doubt you’ll find any cylinder scoring.


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## Ground Fault (Jun 9, 2020)

Thanks for the heads-up about the valve lash. Can you direct me to any resources about correcting it? That square muffler has got to go too. It cracked around the circumference of the inlet pipe where the pipe goes into the muffler, it is leaking hot exhaust gas upwards and will become a problem real quick with the plastic tank. I can use the S-shaped pipe though, and after that I can pretty much create any exhaust setup needed, the side of the frame provided expansive space to work with. Got any ideas how I can proceed and do it right?


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## iowagold (Jan 22, 2020)

they make that good silicone exhaust hose...
then mount the quiet muffler to the frame with the hose as the isolator for vibration.
hummm
maybe a muffler for an eu7000is??
they are a gx390 or a 390cc engine..
that is a large muffler on them. but super quiet design.
with a good tig welder it would be easy to make adapters.

also walmart makes those pads for old folks.
they call them under pads
click here for the walmart pads
we use them for large machines that like to leak...
11 bucks for a pack of 50..
way cheaper than pig brand units..
we make a velcro to hoses hammock for under the machine.
pretty cool
change them every week till we can get them off site for a big tear down..
that is on machines that rent for over 300+ bucks a day...

small leaks happen...
when you seal it back up use the gray gear oil sealer on this page.
CLICK HERE FOR THE REWORK PAGE WITH SEALERS
that gray sealer works as good as honda bond!
i leave it setup for 24 or 48 hours before filling with oit.
clean both surfaces with green can brake cleaner.

it also works well for super hard to seal rear diff units!
and bike leaks. think harley or yamaha's that like to drip.
that stuff rocks for sure.


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## billc (4 mo ago)

Ground Fault said:


> Thanks for the heads-up about the valve lash. Can you direct me to any resources about correcting it? That square muffler has got to go too. It cracked around the circumference of the inlet pipe where the pipe goes into the muffler, it is leaking hot exhaust gas upwards and will become a problem real quick with the plastic tank. I can use the S-shaped pipe though, and after that I can pretty much create any exhaust setup needed, the side of the frame provided expansive space to work with. Got any ideas how I can proceed and do it right?





Ground Fault said:


> First, thanks for reading this thread. After Rita in 2005 and Ike in 2008, sometime in 2009 I took apart my Powermate 4000 with the intention of checking/replacing the brushes and capacitor. It has sat disassembled, the endbell off of it, under my workbench for 11 years. I estimated at that time that it had somewhere in the neighborhood of 800 hours on it, but could be less. Fourteen days constant after Rita in 2005 and thirteen constant after Ike in 2008, with oil changed every 50-75 hours, plug and air filter as specified. Also used it quite a bit between '88 and 2005, 3-6 hours at a time. Back then power went out quite often out here in these woods and we were not high on the priority list as there is no industry or healthcare facilities. All these years it has been under there in pieces, mocking my existence, projecting guilt upon me for not finishing it up, but I bought a Generac in 2010, so. Now I fear the dependability of the Generac, feel I am living on borrowed time, so it's time to get the Powermate going again.
> 
> Your input is valued greatly. Please take a look at the pictures of the wiring inside the endbell and identify any issues you see. I have the Reliance L14030 30amp 125/250V shore power box with recessed male TwistLock receptacle under my eave to connect either generators, it wired into my breaker box w 6ga multistrand to my breaker box, connection made using a 30amp double breaker.
> 
> ...


did u ever get everthing running correctly?
I got one like this from my fatherinlaw and trying to find a manual


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## tabora (Sep 6, 2018)

billc said:


> I got one like this from my fatherinlaw and trying to find a manual


Sadly, you're a few years too late for easy access to the Coleman Powermate manuals of that era. Is your model number exactly the same as the one described here (454002), or a different one?


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## billc (4 mo ago)

tabora said:


> Sadly, you're a few years too late for easy access to the Coleman Powermate manuals of that era. Is your model number exactly the same as the one described here (454002), or a different one?


yes its the same


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## Ground Fault (Jun 9, 2020)

Yes, I did indeed get it back together. New brushes and capacitor, it runs great. Only fly in the ointment is the exhaust pipe has rusted away from the muffler where it enters it. The exact same one is $256. Some others are $30-ish but may not quiet it down too much. If I ever find my file on this one I will scan the manual in and email it to you.


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