kobelco sk 200 overheating

[Mike L]

got sent to look at said exc. Had been overheating. has a 6bt cummins in it with 8000 hrs. when I checked it out the radiator was pretty plugged up looking so I pulled radiator, had it cleaned and rodded, put in a t-stat (didn't have one), and threw in a new waterpump for good measure. still overheated. figured it had to be a head gasket. pulled head and sure enough it was warped .015 and had a crack. yesterday I put it back together and it still overheated. when I say overheat, I mean climbing to 220 in under 10 minutes and would keep going it I didn't stop machine. put in my mechanical gauge and sending unit to be sure and It read the same. I pulled the t-stat out and unhooked the radiator hoses from the rad. and poured a bucket of water into the bottom rad. hose (suction side). I could pour water in way faster than the water pump could pump it through the engine and I wasn't getting water out of the top hose with very much flow. just for kicks I put the old water pump in just to make sure the new pump wasn't a dud. same result. I thought maybe the belt got routed wrong and the waterpump was running backwards but I could only get the belt on one way, which turns the waterpump counter clockwise. the only thing I can think of now is that I have a blockage in the engine. does anybody have any other ideas before I pull the engine and start disassembling?

 

[Delmer]

Muskrats, definitely muskrats. Happens all the time when you start filling the radiator with buckets of pond water. And I thought this was going to be another amateur overheating question, yikes!

I've never had to do this to an engine, but I like to use a water hose at the same time as an air hose to clean out a radiator. I can't see any reason it wouldn't work with an engine. Rig up some fittings, or just rags, to run a water hose and blow gun into the bottom hose, and let the water run full blast, when the water overflows give it a little shot of air. Repeat with more air each time until the water runs clean. If that fails use a sewer snake to see if you can snag any muskrats.

 

[truecountry]

On the 6bt Hmmmm has any stop leak been added for rad leak ...Ive seen this on a Volvo 120d loader..it took a temp gun hitting all freeze plugs and radiator top and bottom and side to side to find blockage
I found some lye type powder radiator cleaner and fix it took 2 doses and flushes ...I seen a lot of crap come out rust and globs

 

[Mike L]

lol delmer, I wish it were that simple but theres been no pond water put in it that I know of. that's a pretty good idea of using compressed air and a garden hose. unfortunately right now its about a mile back in the woods, and I don't have a hose that long. I heard today the owner may load it up and bring it to my house to work on, to save me the 104 mile ride one way. true country, I don't know if its had any stop leak put in it but its a good possibility. Do you remember the name of the flush you used?

 

[truecountry]

lol delmer, I wish it were that simple but theres been no pond water put in it that I know of. that's a pretty good idea of using compressed air and a garden hose. unfortunately right now its about a mile back in the woods, and I don't have a hose that long. I heard today the owner may load it up and bring it to my house to work on, to save me the 104 mile ride one way. true country, I don't know if its had any stop leak put in it but its a good possibility. Do you remember the name of the flush you used?

No and I looked it was old style oil can looking had lye powder based flush on one end and other end was neutralizer ..Try this I just asked a friend who is tech at a fleet shop he said try Cascade automatic dishwasher soap ..he would drain the coolant, refill with one whole container of Cascade and the rest was water. Run the engine until hot then drain and flush/rinse with plain water.use a white clean bucket to catch soapy water and see what comes out

 

[simonsrplant]

May not help but I've used dishwasher tablets with really good success in cleaning both rads and blocks. If there is a choice get the branded ones! Do not use powder as it foams up!
(Also good for cleaning out oil residue when coolers fail)

 

[Delmer]

I've never heard of powder foaming up, that wouldn't work very well in a dishwasher. In the US dishwashing detergents have changed recently, no more phosphorus. You can still get TSP trisodium phosphate online, or lye is available at hardware stores etc. Sodium silicate cleaners are also readily available. All of these, including dishwashing detergent, are nasty on aluminum, so take your chances or use a product designed as a flush, which hopefully protects the metals to some degree.

 

[Pane]

G'day

And that people is why I love forums like these, I've learnt something today. Dishwasher tablets!!!

I've done the compressed air thing with proper fittings and taps to let te air in slowly or fast. I however was taught to do this from the t-stat backwards. Reason being anything that came from the suction side would get stuck so blow it back out the way it came.
Also done this on ski boats with raw water cooling running in weedy waterways. Works a treat.

Cheers

 

[simonsrplant]

Delmer, not sure what the difference in eu to us tablets and powder is.
Had a customer use cheap powder rather than the "secret" fairy tablets I use, took hours to get the foam out...
G'day Pane, yeah, I was talking to a proper old school cat fitter, this fella has probably forgotten more than I know. A real master. Anyway, he told me about dishwasher tablets to clean up the mess after an oil cooler $hits itself. So I tried it. Couldn't believe how effective to was. Way better than the flushing products available.

 

[overworked]

Mike are you getting any circulation from engine to radiator, heater, bleed hose to top of radiator?

 

[Delmer]

Delmer, not sure what the difference in eu to us tablets and powder is.

Come to think of it, your formulas probably changed years before ours did. I'll remember to use the tablets, or use both and compare.

 

[Mike L]

Overworked, when it is all together I have can see zero circulation looking into the radiator. I then unhooked the radiator hoses and turned the lower hose upside down so I could pour water straight into hose. I could pour water in way faster than the water pump could pump it out. That's why I think the blockage is in the engine.
I've never thought of using tablets. I've used cascade powder for quite a while after a oil cooler failure and had good results. I was always told to avoid the liquid soap due to foaming. Is dish detergent strong enough to loosen a blockage? I was also thinking about drano but was worried about it being too caustic and eating liner seals, etc.

 

[simonsrplant]

Not sure tablets would sort a blockage. I guess the combination of air pressure each way and tablets in the system can only help.
Not sure if it would benefit but I would consider laser temp gauging the heads and each respective jacket area of the block to try and trace any blockage to an area, any consistency in reading may point toward something simple that you may have missed or other blockage.

 

[Mike L]

excavator got delivered to our pit for me to work on this week. going to fill block full of water and radiator flush and then build a fitting to fit in the rad. hose to hook up air and try to flush that way.

 

[Mike L]

well after much flushing and not getting anywhere, I pulled the engine yesterday and brought it home. I unloaded it and set it on blocks to be pressure washed. when I set it down, I noticed the damper on the front of the engine moved. I reached down and grabbed it and there was my problem. the pulley had broken away from the damper and spins freely from the damper. when the belt is on, it puts enough pressure on the pulley to spin it, but still slips enough not to let the water pump and fan turn at the right speed. whodathunk?

 

[overworked]

Are you gonna go through it while its out? Thats why I tell them "the diagnosing is done when its back up and running". It's sometimes hard to see the final straw in the bale

 

[Mike L]

overworked, the rancher that owns it doesn't want to spend any money he doesn't have to so i've ordered a new damper for the front and a coupler for the rear. he only puts a couple hundred hrs a year on it so I can see his side of it.

 

[overworked]

I understand, thanks for sharing this info, it makes alot of sense,