PT 1845 Overheating

Charlie_Iliff · Jul 27, 2002

Those reading the blade test thread know that both Sedgeqood and I have had some engine overheating during heavy mowing at hot outside temperatures. There was discussion in that thread about the increased load if four blades per spindle contributing to the problem, which it seems to do, I think both by increased load and by blowing more clippings and dust into the air. With only two blades per spindle, I've never overheated mine, but have had the temperature start to climb, after which I have found at least some dust and debris on the oil cooler. For a while, now, I have blown out the engine oil cooler after each session.
Today, I duct taped some screen over the expanded metal in the engiine cover. After 15 minutes of mowing, the attachment shows what stuck to the screen opposite the engine fan. Without the screen, part or all of that would have stuck in the oil cooler, as would some that fell off the screen while I went to get the camera.
Tomorrow's supposed to be over 90. It will be a good test day to see if the screen by itself causes overheating.

MossRoad · Jul 27, 2002

Wow, that's a tough decision. The screen could block quite a bit of airflow, but since it is spread out over such a large area it might stop more debris in the cooler which might be causing more overheating ... That made no sense /w3tcompact/icons/tongue.gif

My guess is that the debris in the oil cooler probably causes more harm than the amount of airflow that you are going to lose with the screen. (that sounds better) /w3tcompact/icons/smile.gif

Let us know what you find.

marrt · Jul 27, 2002

Charlie,

Where is the oil cooler located? Is it behind the fan? Would you mind taking a few pictures of the engine compartment in general and the oil cooler specifically? Is it possible to add an auxiliary fan (I think the Deutz has a powerful alternator that could easily run an auxiliary fan)? Not sure if this would help though. What about an auxiliary oil cooler with fan? The Deutz is oil cooled, not ail cooled, right?

Also, out of pure curiosity, where is the engine manufactured? I know that Deutz is a German company. Is the engine made in Germany?

duane · Jul 28, 2002

Charlie,

I've read posts where the other tractor brands have had issues with debris clogging the radiators and causing over heating. Imagine how much work your engine air cleaner is doing. Some type of self cleaning screen would be nice.

Duane

wasabi · Jul 28, 2002

Charlie,

While I haven't experienced significant overheating of the 45hp diesel in my PT 2445 (also don't yet have a mower), it strikes me that a separate oil cooler, similar to the one used to cool down the hydraulic oil, could easily enough be routed in to the existing engine oil loop, perhaps between the existing cooler and the return fitting on engine.

I can't quite tell by looking at your configuration, but would guess that such a unit (basically a small radiator and fan), could be mounted along the top of your rear compartment to blow back so as to help blow debris away instead of attracting it. I doubt the small draw of a 12 volt fan would pose a problem for the alternator.

Oil cooler units are available in various sizes...and I can't see why it would matter what brand. Unlike the hydraulic system, where any impedence of the oil pressure might impair performance, I think the only factor here might be the need to add oil volume to make up for that in the new cooler loop.

What do you you guys think?

Charlie_Iliff · Jul 28, 2002

Mossroad, Marrt & Wasabi: Your posts echo my thought processes. After today's tests, it's time to get to Power Trac and work on modifications.
The fan sucks air from the expanded metal back of the cover. The oil cooler iis mounted horizontally beside the engine, so air goes forward into the chamber under the cooler, then up through the cooler. After it goes out the top, a baffle plate directs it out the left side.
Today, with ambient ar 90, climbing to 91 as I ran, the gauge went slowly to 240, the alarm went off, and I pulled to idle. I noticed the hydraulic cooling fan wasn't running, which is a separate problem that I haven't yet solved.
Attached is a picture of the mat of stuff on my screen.
I am sure someone will be tempted to say my screen and the mat blockage caused the overheating. It did, but without the screen the same stuff would have plugged the cooler. Some screen design work is needeed, as is a supplemental cooler.

Charlie_Iliff · Jul 28, 2002

Duane: The other tractors I've worked with all have screens in front of the radiators, which need periodic cleaning. On my old Jacobsen front mower, the intake is in the rear, like the PT, so it gets a lot of dust. It has a two stage filter, first coarse, then quite fine mesh. Of course, when those clog, it overheats 'til we clean them. The PT has no screen whatsoever, although it has a large air cleaner for the engine intake.
Time for some engineering, but I havan't figured how to make it self cleaning. Any suggestions?

deadstick · Jul 28, 2002

Charlie,

Just a question on your picture there. Is that light standard with the machine or did you mount it yourself. I assume it is some warning light when reversing??

Charlie_Iliff · Jul 28, 2002

Chris: The rear light is a factory installation. I don't know how many models they offer it on. I bought the 1845 at the factory right after the price drop in January and it had some stuff on it which may now be options

Charlie_Iliff · Jul 29, 2002

Marrt:
I don't know where the engine is actually assembled. I have been assuming that it is in Germany.
The oil cooling system is obvoiously set up for differing applications, with a rubber intake adapter to mate to ducting or to stand alone with a snap in plastic grid to keep out small animals and hands and feet.
I have sent a long e-mail to Terry Estep at PT explaining my test and suggesting that the machine needs both a filtration system and a supplemental cooler for a bit of excess capacity.
I am hoping they take the suggestions as constructive and not just criticism of the machine. Most times I really like it, but yesterday was 96 degrees when I was working on the overheated engine. Unlike the true macho tractor types, I've never learned to like working on hot stuff in hot weather.

marrt · Jul 29, 2002

Charlie,

You may want to check out <A target="_blank" HREF=http://www.enginaire.com/prod01.htm> Enginaire</A>. I bought one of these for my 425 but haven’t put it on yet. The design of the precleaner make’s it self cleaning. It uses the air intake to set up a centrifugal force to expel heavy material out the sides. You may still have to use some type of screen to catch the large, but light, material.

I know that some folks have used dryer hose to mount the device outside of the engine compartment. Enginaire also makes filters that can be used with the precleaner. You mention that the oil cooler has “a rubber intake adapter to mate to ducting.” This could perhaps be adapted to connect a hose leading to a filter and precleaner (nothing a little more judicious use of duct tape couldn’t handle).

Without a precleaner, I’m concerned that a filter alone wouldn’t be much help as it would just clog up like the oil cooler.

marrt · Jul 29, 2002

My oil cooler on top of the engine compartment looks the same way after mowing my field. When I shut the engine off, the grass falls down on the muffler and starts to smoke. I am afraid it could actually catch on fire. I was thinking of wrapping the entire inside of the engine compartment in screen.

Charlie, I seem to recall you live in MD. I live in NoVA. We had rain Saturday and I noticed a lot less dirt/dust/flying grass when mowing Sunday. If you also had rain Saturday, imagine how much worse the grass accumulation would be after a dry spell. I agree that something needs "fixed."

Charlie_Iliff · Jul 29, 2002

<font color=red>You may want to check out Enginaire.</font color=red>
Marrt: That or similar technology is certainly worth a look. I need one about a foot in diameter, followed by a fine mesh.
For the imediate future, I'll knock the dust off my insect screen every half hour, and see if Power Trac can do some effective remedial engineering. I'd try a few things, but my time will be sorely limited in August. (And of course today is predicted to be 98 degrees, so I don't mind sitting in my office.)

MossRoad · Jul 30, 2002

Yeah, that would most likely get caught up in the coolers had the screen not been there.

As far as a self cleaning screen goes, it would probably cost way more than its worth. Have you looked into a small 12v compressor with automatic pressure shutoff that you could mount on board? You could plug the ends of your trailer hitch tube and make it into an air tank. A short hose and blow gun could make quick work of the screen debris in the field.

My hydraulic cooler fan has worked flawlessly so far, but this seems to be a weak point in the PT for all series as several of us have reported hydraulic cooler fan troubles in the 400 series as well. Please let us know what the cayse/cure is.

Charlie_Iliff · Jul 30, 2002

MR: You suggested:
<font color=red>You could plug the ends of your trailer hitch tube and make it into an air tank.</font color=red>
Reminds me of the time AJ Foyt got caught with the roll cage sealed and full of nitrous oxide. It would have made a spectacular fire if he'd had a wreck and it had leaked.
When I get the carryall built, it would not be a problem to put an air tank on it. Of course, at my current progress rate, the carryall may be done about 2004. I hadn't thought of an onboard compressor, though.
Terry will mull over what I wrote him and call me. I'm hoping that they will agree that a real filter system needs to be developed. I would think a variant of my external screen wire system, coupled with a finer filter in line, and probably another cooler in the top of the compartment would be a genuine fix. The inside of the oil cooler is so busy that even compressed air doesn't get every bit of debris out.

MossRoad · Jul 30, 2002

/w3tcompact/icons/laugh.gif I've never heard that one about AJ. KaBOOM!

Charlie_Iliff · Aug 1, 2002

Re: PT 1845 Overheating- Fan

I talked to Terry today about the hydraulic fan sender. He told me to look on the inside of the right rear of the engine compartment, on the frame below the electrical junction box. He said that I could test it with a heat gun. Turn on ignition, heat, and fan will come on.
Turned out the heat gun test wouldn't have worked. Of course, once I plugged the loose wire back on the temperature sender, it probably would have worked fine. I jumpered the wires and the fan ran, so there isn't much question that the disconnected wire was the problem.
The real trouble is that I don't have anyone else to blame./w3tcompact/icons/mad.gif I almost certainly knocked the wire off with the shop vac. See if I ever clean again. I should have known it would cause trouble./w3tcompact/icons/laugh.gif