Thermostat check

phildac

Member

Equipment
1984 B8200E, L260F
Jul 29, 2009
203
1
16
Wentzville, MO
Hey all,

Still working on the L260 I picked up a few weeks ago. Having the radiator boiled out and checked/repaired for leaks. Figured I would check the thermostat to see if it was in need of replacement and here is what I found...



Is there any damage that could have been done from running without? Other than not running at the "ideal" engine temp?

Thanks,
Phil
 

kuboman

Member
Dec 6, 2009
725
4
16
Canada
Its not the best for an engine because the engine doesn't get hot enough to boil out the condensation and acids in the oil. Depends how long it was run that way. One way to tell is to look inside the valve cover and see how much sludge has built up.
 

85Hokie

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Its not the best for an engine because the engine doesn't get hot enough to boil out the condensation and acids in the oil. Depends how long it was run that way. One way to tell is to look inside the valve cover and see how much sludge has built up.

Never a good idea to bypass using a thermostat.......what Kuboman said is very true. Also the water ONCE hot, runs by the block and head at a higher rate, thus not allowing time to pick up the heat correctly and then cooling off.
Someonw must had a stuck one, threw it out and said wth and closed it back up, would be really bad in the winter. Do what Kuboman says and buy you a new stat and gasket.
 

phildac

Member

Equipment
1984 B8200E, L260F
Jul 29, 2009
203
1
16
Wentzville, MO
There is quit a bit of sludge/oily soot in the exhaust ports and on the valves. Ordered a new thermostat and gasket today. Will some of that sludge burn off over time after the thermostat install? Does it hurt anything to leave it like that? I wish I could clean it without having to take off the head. New head gasket is over $200.

Thanks for the info!
Phil
 

85Hokie

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There is quit a bit of sludge/oily soot in the exhaust ports and on the valves. Ordered a new thermostat and gasket today. Will some of that sludge burn off over time after the thermostat install? Does it hurt anything to leave it like that? I wish I could clean it without having to take off the head. New head gasket is over $200.

Thanks for the info!
Phil
I would think that the "oily soot" would be a normal thing in a diesel exhaust port.........the sludge would be the not so good thing. I am not a thermodynamic engineer....but if the engine got up to a "good" hot temp, then over time it might burn some of that stuff off.....but then again....maybe not. A diesel mechanic will jump in here and tell the real story!:D
 

85Hokie

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Here are some pics of the two exhaust ports and then the intake port.

wonder if there are pictures of a "normal" port and what it is supposed to look like?

also wonder if there is something that can be added to the fuel to help clean that up, I am just now getting into the diesel world, so i am not savvy to all the ins and outs of diesel conditions. Someone will chime in here and give you some good advice as to what to do or "not" do !
 

phildac

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Equipment
1984 B8200E, L260F
Jul 29, 2009
203
1
16
Wentzville, MO
I did have the valve cover off and there was a small amount of watery sludge in there and in the valve cover itself. I cleaned it all out and am waiting on a new valve cover gasket. The soot in the exhaust ports isn't watery just a slight bit oily which is guess is to be expected.

Had the valve cover off because the decompression lever was not working right. Seems like whoever had it off last didn't bother to line up the lever correctly which I think caused it not go fully closed, making it hard to start and causing unburned fuel to pass through.

On a different note, I went to change the fuel filter and it looked like it was somewhat newer, but it doesn't matter if the filter is there when the spring and the cup that goes on top of the spring are not in the bottom of the filter cup. Basically the filter was just sitting in the bottom of the filter cup and letting anything go right through to the injector pump and to the injectors. Luckily there is a Gozui screen filter pre fuel pump which blocks the big stuff. I took that out to clean it and it was super dirty. Should have taken a picture.
 

85Hokie

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I did have the valve cover off and there was a small amount of watery sludge in there and in the valve cover itself. I cleaned it all out and am waiting on a new valve cover gasket. The soot in the exhaust ports isn't watery just a slight bit oily which is guess is to be expected.

Had the valve cover off because the decompression lever was not working right. Seems like whoever had it off last didn't bother to line up the lever correctly which I think caused it not go fully closed, making it hard to start and causing unburned fuel to pass through.

On a different note, I went to change the fuel filter and it looked like it was somewhat newer, but it doesn't matter if the filter is there when the spring and the cup that goes on top of the spring are not in the bottom of the filter cup. Basically the filter was just sitting in the bottom of the filter cup and letting anything go right through to the injector pump and to the injectors. Luckily there is a Gozui screen filter pre fuel pump which blocks the big stuff. I took that out to clean it and it was super dirty. Should have taken a picture.
Sounds like the PO did not know nor care for what he/she was doing with that machine! Hopefully a little TLC will get it up and running. The watery sludge is a concern...........i would think that the PO took the thermostat out due to overheating?Thinking it would help. And the sludge might be from a blown head gasket? just a SWAG............
 

85Hokie

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I did have the valve cover off and there was a small amount of watery sludge in there and in the valve cover itself. I cleaned it all out and am waiting on a new valve cover gasket. The soot in the exhaust ports isn't watery just a slight bit oily which is guess is to be expected.

Had the valve cover off because the decompression lever was not working right. Seems like whoever had it off last didn't bother to line up the lever correctly which I think caused it not go fully closed, making it hard to start and causing unburned fuel to pass through.

On a different note, I went to change the fuel filter and it looked like it was somewhat newer, but it doesn't matter if the filter is there when the spring and the cup that goes on top of the spring are not in the bottom of the filter cup. Basically the filter was just sitting in the bottom of the filter cup and letting anything go right through to the injector pump and to the injectors. Luckily there is a Gozui screen filter pre fuel pump which blocks the big stuff. I took that out to clean it and it was super dirty. Should have taken a picture.
Have YOU had it running yet??????? and if so, does it run ok? You said it was hard to start.........
 

kuboman

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Dec 6, 2009
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16
Canada
A good fuel conditioner and lots of work will clean it up. You will need to increase the oil changes as most of the sludge will end up in the oil.
 

phildac

Member

Equipment
1984 B8200E, L260F
Jul 29, 2009
203
1
16
Wentzville, MO
85Hokie,

The guy had it running when I showed up to pick it up which had me leery right off the bat. The guy had bought it to restore but never got around to it. He said the previous owner before him had it sitting in a barn for several years. What if any of that is true, I have no idea.

The guy got it to a running state to sell I guess and that was about it. When I got it back home I was unable to get it started. Weak battery, old glow plugs and the decomp lever issue I guess all played a part.

After fixing the decomp lever, I was able to get it started after a couple of tries and only ran it for less than 10 seconds since I had the muffler/manifold off. So I have some good confidence that I will be able to get it started again once all back together and with a new battery(current one reads 11volts), new glow plugs(installed), decomp lever fixed and new fuel/oil and filters.
 

phildac

Member

Equipment
1984 B8200E, L260F
Jul 29, 2009
203
1
16
Wentzville, MO
kuboman,

I plan on changing the oil after I run it for an hour or two. I'm sure there will be a bunch of sludge that will work it's way loose and will dirty the oil quickly. Im going to do the same with the coolant. I'm hoping a head gasket change is not in my future.
 

85Hokie

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85Hokie,

The guy had it running when I showed up to pick it up which had me leery right off the bat. The guy had bought it to restore but never got around to it. He said the previous owner before him had it sitting in a barn for several years. What if any of that is true, I have no idea.

The guy got it to a running state to sell I guess and that was about it. When I got it back home I was unable to get it started. Weak battery, old glow plugs and the decomp lever issue I guess all played a part.

After fixing the decomp lever, I was able to get it started after a couple of tries and only ran it for less than 10 seconds since I had the muffler/manifold off. So I have some good confidence that I will be able to get it started again once all back together and with a new battery(current one reads 11volts), new glow plugs(installed), decomp lever fixed and new fuel/oil and filters.
I hope you got it at a verrrry good price?:D
I know that you will have the ol girl singing in a while!
 

phildac

Member

Equipment
1984 B8200E, L260F
Jul 29, 2009
203
1
16
Wentzville, MO
85Hokie,

Yeah, picked it up for $760 on eBay and about $200 in fuel to go get it. With parts, manuals and fluids, I'm into it for around $1300 and whatever the radiator boil/repair cost me. Hoping to be done for under $1500.
 

D2Cat

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Mar 27, 2014
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Had the valve cover off because the decompression lever was not working right. Seems like whoever had it off last didn't bother to line up the lever correctly which I think caused it not go fully closed, making it hard to start and causing unburned fuel to pass through.

.
Phil, you mentioned your decompression lever wasn't working correctly, and you have the valve cover off. There's an "0" ring in the housing at the front end that could be dry or dirty on the shaft between the VC and the arm the cable hooks to. Once you have the shaft turning freely, and in the correct position in the valve cover be sure to adjust the screws (on top of the valve cover) to adjust the valve to the correct position when open and closed.
 

phildac

Member

Equipment
1984 B8200E, L260F
Jul 29, 2009
203
1
16
Wentzville, MO
D2Cat,

The Decomp lever is free, the PO just didn't have the lever in the right position when they put the valve cover back on. I know it is on correctly now so when I get the valve cover gasket it should be good to go. Thanks

Phil