CAT D6R fuel in coolant?

[Plan B]

Im working on a Cat D6R and it keeps getting fuel in cooling system which destroys the rubber seals under the radiator sections. Can someone tell me how this happens?

 

[Per Eriksson]

Bad seals on the injector sleeves, only possible place.

 

[Nige]

Bad seals on the injector sleeves, only possible place.

+1 Seen it many times on various C-series engines. In my experience it's impossible to pull the injector sleeves with the head installed on the engine as per the Cat procedure. Even dealers generally pull the head and bash the sleeves out from below. I take it the engine is a C-9 ..?

If the fuel contamination was really bad you may have to replace every rubber component in the cooling system (flexible hoses, radiator core seals, etc) because the fuel in the coolant will have softened them to something that looks like jelly.

 

[big ben]

I just replaced a set of injector cups on a D6 head and it can be done with the head on the block. The Cat tool kit for the job comes with a big tap to cut threads into the cups and then pull them up with a puller threaded into the newly cut threads !

 

[Lee-online]

I have replaced cups and have never pulled the head to do it. We have the correct tools though.

The fuel does soften the rubber so you should replace all the hoses and seals in the rad.

To flush the cooling system, use liquid cascade and water. do this a few times and it will clean up.

also drain the sediment out of the fuel tank to make sure there is no coolant in it.

 

[Plan B]

Cool thanks for the info ive already removed the radiator sections and seals which were destroyed and i had to fish out all the rubber pieces from the sections and the bottom radiator tank. Im gonna flush the system out after i check all the hoses and what not and put it all back together then pull the injector cups and replace them. Thanks again!

 

[Plan B]

Another question. When replacing the rubber seals on the radiator sections, i put the seals in the bottom housing first and put alittle lube on them and tried putting the sections in. But they wont go all the way in! Are they supposed to go all the way down flush? Ive tried prying them down with pry bar and they just come back up when i let off. So i just tightened the upper brackets which pushed them down but not all the way. Will they seal off like that or do they have to go all the way down?

 

[Nige]

They are supposed to go all the way in before you tighten up the hold-down bracket on each core. I take it your cores are the square ones with 2 tubes on the bottom of each core, correct..?

If you push the radiator cores like you have been doing the chances are the tube at the bottom of the core will tend to either drag the seal into the bottom tank with it, or stretch the seal. While they may seal now they'll probably start to leak very soon. The best thing I have found for installing radiator cores is Caterpillar 5P-3975 Rubber Lubricant. Don't under any circumstances use vaseline or any similar petroleum-based product.

Clean the bottom tank until it is shiny and perfectly dry, then install the seals dry into the bottom tank. Apply the lubricant to the bottom of the radiator core tube(s) and to the inside bore of the seal. Present the core to the seal and it should literally almost fall into place under its own weight without needing pressure. You will then need to put a bit of pressure on the core from the top to get it to go maybe the last 1/4" or less until it's butted up in position. At that point install & tighten the hold-down brackets and you're home free. Cat use a special tool to clamp down radiator cores that is basically a vice grip with a hugely wide pair of jaws on the bottom of the core to clamp it in place so that the hold-down brackets can be installed. Using that tool it's basically a one-man job, you don't expecially need the tool but it then most likely becomes a 2-man job. One guy holds the core down with a bar while the other one tightens the hold-down.

 

[Plan B]

Yes it is the square ones with the two tubes on bottom. Well i did put a little lube on them so its too late to use that cat rubber lube...oh well! I used a pry bar on the section while i tightened the hold down clamp. The went down but were like less than 1/4 inch from being flush yesterday but today they were all the way down! I guess they slid on in with that constant pressure from the hold downs. Anyway, why does CAT have to have a special tool for every stinkin thing!!!! I bet they make as much money on special tools and lubricants as they do on selling machines!! Thanks for the info I will use it next time for sure...lol!

 

[Nige]

As I said above the special tool just makes it a one man job ........

I hope you didn't use a petroleum-based lube on the seals otherwise you'll be pulling them out again PDQ when they dissolve and start leaking.

 

[Lee-online]

I found that liquid soap works best to lube the seals. Apply it to both sides of the seals and the rad core. Push the core in and i put pressure on the lower lip of the core with my foot and rock it to seat it. Then I install all the brackets and pry the core down before I tighten the brackets.

 

[Plan B]

Ok now i gotta replace the cups. Ive got the tool to pull the cups but i cant even get the injectors out!!! Special tool?

 

[Nige]

Nothing special - 90-degree pry bar under the part of the injector where the hold-down bolts are.

 

[Plan B]

I tried a regular heel bar but it wasnt long enough so i got an adjustable heel bar at napa that worked great!! I changed out the cups which wasnt so bad, hardest part was cutting the threads. Put everything back together and filled coolant ran machine and had no problems.

 

[MrKomatsu]

Komatsu rules..........lol....i 2 have had the d6r uel in coolant problem......fuel tubes were cracked.....ouch

 

[250c]

Autozone carries a radiator hose lube that I've found handy on coolant rubber.

 

[ETMF 58 White]

I've got to reinstall two radiator cores tomorrow on my 5LN D6R, assuming the radiator shop can fix the hairline crack I see along the bottom edge of the outside core where it's been rubbing a little bit against a rubber baffle. Had to pull the number 2 core first to give me a little more room to get number 1 out. (Or maybe I've got number 6 and 7 out; it's the two far right ones on the machine--far left if you're standing between the blade and the radiator.

Anyway, I've got two different kinds of Murphy tire lube in the shop that I use to mount truck tires. One is a bucket of greasy stuff that smears on the tire beads with a little mop, and the other is some blue stuff that I mix about half with water and have in a squirt bottle. Will either of these work to lubricate the bottom core seals? And can I make new little connecting hoses for the cores from 1/4 fuel hose? My present ones are a little stiff from age and now is a good time to replace them.

If the radiator shop thinks my core is not worth fixing the crack, I guess I'm off to the Cat dealer to buy a new one for $560 each. The problem with that is that all seven of them are likely the same age and degree of deterioration. Truthfully, they all look pretty clean so I'm hoping it's just a problem caused by the chafing of the outside cooler against the rubber side baffle.

 

[Cmark]

I always use the approved Cat rubber lubricant, part number 207-1601. It does a great job and dries without leaving any residue. We keep a spray bottle of it in the service truck. Handy for installing radiator hoses, rubber tracks, anything like that.

The small connecting hoses can be bought from Cat for little money and they are ready shaped to fit. You can get them when you go to buy your new seals for the cores. You are buying new seals, right? Please don't try to reuse the old ones, you'll probably regret it.

 

[Nige]

I'd also recommend the Cat lube. You have to be very careful with those radiator core seals not to get anything on them that has the slightest trace of mineral oil in it or they will swell and leak. The small hoses joining the cores cost pennies and while you're at it I'd recommend replacing the hose clips that fix them to the cores. Lastly, I have no idea of the exact age of your tractor but you have a model that went out of production in 2003, 12 years ago. If you have already removed 2 cores out of the radiator personally I'd pull the lot and fit new seals to all of them bearing in mind the age and heat to which they've been subjected over the years. The additional effort as you already have 2 cores removed will be minimal. With those radiators it's best to start installing cores from the outside on both sides and work to the centre.

 

[Cmark]

and then while the cores are out, you may as well do the fan drive bearing, and check the crank damper, oh, and lets do the front crank seal as well, and, oh your god! where will it all end? FFS I only started off with a bloody coolant leak.

Dontcha just love this business :thumbsup: