MEP-003 Water in Exhaust

[GAPRIME]

Thanks Ray,

Do I need to remove the large cap whilst it sitting in acetone?

These days due to the rising cost of an IP Its best to just remove the pump. It will tolerate about ZERO amount of rotation if its frozen.

OR, IF you have an Ambac M50 pump you could remove the fuel line from the filter assy. raise it up above the level of the IP and fill it with acetone. Remove the large cap in the center of the IP, then remove the 5/8" 12 point cap under it and expose the delivery valve. Remove delivery valve and holder. Once the IP is full of acetone you should get some leaking out of the delivery valve area. replace the delivery valve, holder, cap and large nut.
Add more acetone to fill the raised up fuel line.
Let it sit a week while the cylinder lube is doing its job.
After a week check the throttle linkage to be sure it is moving free. If not, do not rotate engine.
If the linkage is free you have an 80% chance the pump is free.

IF you have a Bosch PSU pump I would not recommend taking a chance. if you are unsure if it is free and it is not free, it will 100% surely break when you rotate the motor. As Ray C. said, the PSU is NOT Repairable and these days it will cost you at least $750 to replace the pump.

If you leave the IP in place, you can try rotating the motor a little, then rock it back and forth.
Then remove the caps and delivery valve holder again. if the plunger is free it will rotate as you turn the engine. It will also move in and out while rotating.
You can lightly tap the plunger with a brass punch to see if it is sticking outward. Brass punch will push it in against the cam lobe if it is stuck out.

Once things are freed up and engine is turning you can move on to inspecting the cylinder walls to see what you need to do next.

 

[Ray70]

I would leave it on. That way the acetone will stay in the pump body and do it's magic.
As a point of reference, does the gear on the face of the pump spin freely or is it stuck, and is the throttle lever free or binding / stuck?

 

[GAPRIME]

Ok. Thanks

The gear does turn but it requires some effort. The throttle lever moves freely

I would leave it on. That way the acetone will stay in the pump body and do it's magic.
As a point of reference, does the gear on the face of the pump spin freely or is it stuck, and is the throttle lever free or binding / stuck?

 

[Chainbreaker]

If you have confidence that you can bring this unit back to life and want to do the cylinders right, you should consider buying the complete top end Cylinder Gasket Kit. There are currently some listed on eBay. Try using a search something like: 110-2460, Onan Cylinder Gasket Kit. MEP002A , MEP003A 110-3635, Onan Head Gasket, 2 ea glow plugs.

Looking at the pictures they include: valve cover, cylinder head & exhaust gaskets, push rod tube O-rings + glow plugs. You could probably get the qty (2) required for ~$200. Just the 4 glow plugs included would typically cost that much.

 

[GAPRIME]

Yes, I think if i can put it all back together it will work. I will need continued guidance from you guys.

Thanks for the tip about the kit - Wish I had known earlier - I had bought some of them individually already but I will buy this kit as well. Just for your information that kit is now listed for $149 but I will still get it if it comes with new glow plugs

If you have confidence that you can bring this unit back to life and want to do the cylinders right, you should consider buying the complete top end Cylinder Gasket Kit. There are currently some listed on eBay. Try using a search something like: 110-2460, Onan Cylinder Gasket Kit. MEP002A , MEP003A 110-3635, Onan Head Gasket, 2 ea glow plugs.

Looking at the pictures they include: valve cover, cylinder head & exhaust gaskets, push rod tube O-rings + glow plugs. You could probably get the qty (2) required for ~$200. Just the 4 glow plugs included would typically cost that much.

 

[frank8003]

Kroil can be your your friend with this

 

[Chainbreaker]

... Just for your information that kit is now listed for $149 but I will still get it if it comes with new glow plugs

The lister apparently has several in stock. If you use "Make an Offer" when buying 2 sets its likely he might accept the suggested offer. I recently bought 2 myself & my offer was accepted. Good luck!

 

[Ray70]

So how bad is the cylinder wall on the worst bore? It looks pretty bad in the pictures, but I know pictures of cylinders can be deceiving.
Do you have large pitted spots that you can catch with your fingernail, or is it mostly just discolored but fairly smooth?
The other thing to check for is stuck piston rings. You want to try to make sure they are free within the piston grooves and not stuck to the piston.

 

[GAPRIME]

Hi Ray,

Yes it was rusted but honing it made it smooth to touch and the pistons move freely with little effort when you rotate the flywheel. The pictures show some discoloration.

How do I check for stuck piston rings?

So how bad is the cylinder wall on the worst bore? It looks pretty bad in the pictures, but I know pictures of cylinders can be deceiving.
Do you have large pitted spots that you can catch with your fingernail, or is it mostly just discolored but fairly smooth?
The other thing to check for is stuck piston rings. You want to try to make sure they are free within the piston grooves and not stuck to the piston.

 

[Ray70]

One thing you can try as a crude test is to put the piston near the bottom of the bore, finish your movement with a slight up stroke movement, so go slightly past the bottom until the piston starts to rise again then stop.
Put fluid on top of the piston, something like diesel, HHO or kerosene.
See if it quickly drains past the rings of if it will stay there.
It will drain very slowly, but I would expect 1/2" of liquid to last a good several hours, but maybe not overnight. If it's gone in like 30 minutes I would suspect the rings are not sealing well. If it stays all day that would be great. If its gone in 10 minutes I'd probably plan to pull the pistons out.
Test it and see what happens and we'll discuss from there.

 

[Guyfang]

You also need to read the TM, as it tells you the Army way. Between that and Ray, it should not be hard.

 

[GAPRIME]

Thanks for the tip Ray.

I did notice that it took over a day for the MMO and Blaster mix to drain even after cleaning out the rust in the cylinder. It definite held the fluid without any appreciable loss in 10 miniutes. I will redo it with diesel just in case the viscosity is significantly different and report back.

One thing you can try as a crude test is to put the piston near the bottom of the bore, finish your movement with a slight up stroke movement, so go slightly past the bottom until the piston starts to rise again then stop.
Put fluid on top of the piston, something like diesel, HHO or kerosene.
See if it quickly drains past the rings of if it will stay there.
It will drain very slowly, but I would expect 1/2" of liquid to last a good several hours, but maybe not overnight. If it's gone in like 30 minutes I would suspect the rings are not sealing well. If it stays all day that would be great. If its gone in 10 minutes I'd probably plan to pull the pistons out.
Test it and see what happens and we'll discuss from there.

 

[GAPRIME]

Hi Guyfang!

Thanks for the tip.

I have checked the following manuals but did not see what you are referring to - did I miss something or is there another TM that I have missed?

TM-5-6115-585-34
TM-5-6115-585-12

You also need to read the TM, as it tells you the Army way. Between that and Ray, it should not be hard.

 

[GAPRIME]

Thank - I did not know that. Not to worry - I have already bought it for 149 each

The lister apparently has several in stock. If you use "Make an Offer" when buying 2 sets its likely he might accept the suggested offer. I recently bought 2 myself & my offer was accepted. Good luck!

 

[Guyfang]

The -34 TM explains how to time the IP and engine. Its not hard, and Ray can explain a short cut or two. Its just good to know whats in the -34, because it helps you understand more about the equipment. A long time ago when I did this same action for the first time, I did not pay enough attention to the book, and there was no one to help me. When I got done, the engine would not start, and I felt like jumping from a bridge with my pockets full of rocks. So I went back and read again. The TM explained, if after you have followed the procedures and it will not start, You may have it 180 degrees out of time. I removed the IP, rotated it 180 degrees, installed it and it ran like a champ. Its always better to know and not need, than to need and not know.

 

[GAPRIME]

So I took the heads to the shop to get it cleaned and machined. Just collected them

 

[GAPRIME]

Starting reassembly this week. Any tips from my Guru's are welcome

 

[GAPRIME]

Thank you Guyfang. Any additional tips Ray?

The -34 TM explains how to time the IP and engine. Its not hard, and Ray can explain a short cut or two. Its just good to know whats in the -34, because it helps you understand more about the equipment. A long time ago when I did this same action for the first time, I did not pay enough attention to the book, and there was no one to help me. When I got done, the engine would not start, and I felt like jumping from a bridge with my pockets full of rocks. So I went back and read again. The TM explained, if after you have followed the procedures and it will not start, You may have it 180 degrees out of time. I removed the IP, rotated it 180 degrees, installed it and it ran like a champ. Its always better to know and not need, than to need and not know.

 

[GAPRIME]

Hi Ray,

The IP has been sitting in acetone now for over a week. Anything else you would suggest I do before mounting it back on?

Des

I would leave it on. That way the acetone will stay in the pump body and do it's magic.
As a point of reference, does the gear on the face of the pump spin freely or is it stuck, and is the throttle lever free or binding / stuck?

 

[Ray70]

Just spin the gear, make sure it turns freely now. then push in on the cap where it rides against the cam, it should move in and out freely ( the spring force is tight but you an press it with your thumb )
You could also take out the delivery valve so you can see the plunger movement in and out, if you have any doubts that it's free.
To reassemble, follow the TM. Get the motor to compression stroke of cyl #1, set flywheel to PC mark and align the slot in the pump's drive gear with the screw hole in the side of the pump, hold it in place with a 1/8" drill bit stuck down the hole and into the slot.

IF you have ANY doubt about being on #1 compression stroke, I will get you my secret trick as soon as I get home from work. I can tell by the location of the cam lobes which can be seen through the pump mounting hole. I will see if I can get you a picture in the correct orientation. That way you are 100% sure!