Serial: H5M01334 Hours: 5200-5300, I am not near it at the moment. So, I haven't been using my 305 a lot recently, however I have been diagnosing the A/C issues its had. Lately I've been throwing a can of 134a into it when I need it and it'll get me a few days, which is cheaper than the evaporator it needs at the moment... ANYWAY, I've only noticed it when the A/C is on, and working, even if its not working well, you can hear that the compressor is on, but isn't blowing very cold at all. The engine will bog down under hydraulic load, usually two functions at once, or tracking once its up to temperature. I need to do more diagnostics on it, get coolant temps, and see if anything looks "out of place". I noticed the coolant gauge is above halfway, probably closer to 3/4 across the sweep, but not into the red. I want to say it was around 203, or 205 degrees when I checked it through the display the last time it did it. Either way, I am trying to source the issue of the bogging that it does. I've only noticed it after I have ran it for a while, and its at full operating temperature, and I have no idea if this is relevant, but its also when the A/C is on, the last time it occured, I turned the A/C off, and it did it again, but then I left it sit for about 5 minutes at idle, and went back to it and it was fine. I know when I first start it up, and attempt to perform any hydraulic functions, to say just move it out of the way for something else, it will bog and want to die at idle. Not every time, but more so when its colder, I don't know if thats related. I feel like its temperature related, the fuel filters are good, and I am not losing fuel supply either as the filter never gets drained of fuel as I am operating, so I don't think its the fuel pump. Hydraulic fluid is on the low side of full. There are codes stored in the computer, one is an overheat code, but its from a few hundred hours ago, before I even bought the machine. No warning lights come on either when it is bogging down. I'm trying to see if I am dealing with something serious, like a hydraulic pump, or something stupid, like belt slip, and trying to get direction on where to go before diving into it head first. Thanks!
When it does it again stop the engine and loosen the cap on the fuel tank then listen for a whooshing sound.
Another simple test is to run it off a Jerry Can of fuel and see if it still does it. Simon C
Thinking its vapor locking the fuel tank? Im going to be running it most of the day today, so I will give that a shot!
Take cap off and tape a good rag on top and Nige may of found it. Has to be ruled out before firing the parts cannon. Simon C
Before you kickstart it for the first time take a moment to locate the drain underneath the fuel tank. Remove the plug or open the valve and see what you get out in the way of water and sediment.
I’ll try and find it. Is it under a plate or anything? I’m sure I’ll get a bunch of crap out of it. If it’s as simple as a new fuel cap. I’ll be tickled pink.
You have to start by eliminating all the basics before you go on to the expensive stuff. See the illustration below. It appears as though it's a plug in the bottom of the fuel tank. It does not appear to be under a plate but I wouldn't guarantee it. Regarding the tank cap try giving it a good clean inside and out with aerosol brake cleaner to make sure the vent is clear.
There is a hidden fuel filter, plastic mounted on backside of a bar in the right side compartment. Did u change that filter? I missed it first couple oil changes cause its kinda hidden
Thanks Nige, Looks like it’s an actual plug and not a valve. Yay… And, it’s full of fuel, and the plug is partially covered by the actual base of the house. So I’m going to have to run it down low and see if I can move the tank a little to get the plug out. Yeah. That one is easy to miss if you’re not looking for it. but its fresh too
Bugger. Yes you need to do it when the tank is low on fuel. Meantime try the loosening the tank cap trick next time it bogs and see what happens.
Hopefully the cap does the job. When it’s low on fuel. I’ll try and get that plug out. Maybe when it’s back at the shop in a controlled environment lol
At whatever point you do drain it maybe look at installing a valve in place of the plug.?
Don't be scared, Allen on a extension, pull the plug. Being full and cap on it might hold a vacuum like. Most likely not but have a couple buckets ready and prepare to get a little wet lol
That’s going to be on the list of things to do. Oh I’m not. But I can’t get it out. lol.
What’s the coolant temp supposed to be? Seems to start acting up around 200 degrees and I’m up to 208. It hasn’t done it bad enough or long enough to stop and check the cap.
Not sure but probably the thermostat opens around 90 DegC/195 DegF or around that. Have you inspected and/or cleaned the cooling package (radiator & hyd oil cooler) lately.?
I have recently cleaned it with air. But maybe it needs a good washing with water. I just ran it up to 226°. Left it on high idle and watched the temp drop pretty quick. I’d say I need a thermostat at the minimum. And a good cleaning of the radiator stack. In 6 minutes of idling on max throttle, it’s down to 208° The higher the temp got. The more it acted up. Wondering if it’s derating itself
I suspect that on a machine as small as yours the only way to adequately clean the cooling package might be to remove it and split all the coolers apart from one another. What you find may surprise you.
Oh I’m sure it’s a disaster in between everything.
One thing I learned from on of the better mechanics on here when my Tak TB260 kept creeping up in temp was to make sure the fan belt was tight enough to not slip at high idle. I tightened it more than I thought necessary and solved my issue.
That was my concern as well. I need to check the tension of the belt, but viewing the side of the radiator, it looks to be full of mud.... I ordered some radiator spray nozzle things. They will be here Friday, hopefully I can get this worked through the next few days and just watch the temps. Ill report back if anything else shows up.
Judging by the looks of the parts manual it would appear to be almost impossible to clean the cooling pack with the fan shroud still installed. The one fortunate thing is that the radiator & oil cooler are mounted side by side instead of being stacked one behind the other as they are on many other machines.
Yeah, thankfully they aren't stacked tight and deep like some are. Its just getting that shroud off, or at least trying to get between the shroud and radiators. I bought one of those radiator cleaner bars, its pretty thin and goes on a pressure washer, so I am going to try and see if that'll fit in there. I have a hot pressure washer I can adjust the pressure on, so I don't kill the fins themselves. Worst case scenario, I am pulling the radiators out, and if I am doing that, its getting a water pump, thermostat, and A/C compressor... Ha!
Well. I got the fuel tank low. And I can’t get the tank to budge. So I’ll have to figure out how to loosen all the bolts and move it. But I don’t think I’ll be able to do that without some serious parts removal. It acts up when it’s gets very close to operating temperature and more so when it’s over 195°. Wondering if the hydraulic rad is not cooling the hydraulic oil properly and the pump isn’t happy about it. I received my radiator cleaners so I need to get it somewhere I can work on it now.
I can finally report back on this. It absolutely did it worse with the AC on. Only thing I can figure is that the engine was working just that much harder. HOWEVER! The coolant radiator was probably 50% plugged with dust, mainly around the edges. The hydraulic radiator was probably 75% plugged with mud. I was barely getting any air through it. I had blown it out when I got the machine, which was not that horribly long ago and stopped getting dirt, what I didn’t do was unbolt the AC condenser or the brackets holding it and look behind them or clean really good behind all of that. Once I removed that, I saw the real issue. There was about 1/4” of mud on top of the hydraulic radiator behind the support. Where you had to really look in and see. And it was also behind the air filter housing where you couldn’t see. It was bad. I was blowing air from the engine side of both coolers and wasn’t getting much air on the opposite side. 3500psi of water wasn’t even coming through using those radiator cleaning bars that I don’t suggest using with 3500psi of water. Lol Ended up using the hot pressure washer and going from the outside in and just working my way in, blowing the dirt off and not into the cores with low pressure and then building up to 3500psi. I got a wild amount of dirt out of those coolers. When I was done I shone a light through and could see the light very easily through them. I have yet to run it since the cleaning, but judging by what the hydraulic side looked like, I’m not surprised the hydraulic pump was unhappy. I wish these had a hydraulic temp on them. One thing I will say is, Cat planned for radiator cleaning. The bar on the side of the radiator comes off and gives you direct access to the engine side of the radiator to blow it out. Three 16mm bolts and you can see everything you need. I have a crappy before photo. But I ended up removing the condenser, drier, and air filter housing to gain direct access to the front of the coolers. The support on the right was hiding solid dirt just like the spot 3/4 of the way down but it spanned the length of the support rod. In the after photo, you can see how I removed the brace on the far left of the coolers. I’ll try and get some hours put on it and see how it does. But I am pretty confident those were my issues.
See my Post #18 back on page 1. Colour me surprised - not…. Unfortunately the smaller the machine the harder it is to clean a cooling package without some disassembly being involved.
I cant see that being the issue. Hopefully it was in your case. But I've seen 10x worse and AC worked like it was new and no over temp issues. We had a job last summer the dirt was so dry it was like baby powder, it got in everything. Put water on it and it just turned to mud. It sucked! Never overheat issues on any of the machines, specially the loaders that drove thru it all day.
I always start with air first and most loose stuff will blow out immediately. Not a fun job with dust mask on, but water will sometimes just turn everything into mud unless you work it hard with pressure. At 150 psi of air dirt usually blows out. I have some blowpipes to go down between radiators to help clean out. I have washed a lot of rads after air with a varsol gun setup to first shoot heavy concentrate degreaser in boiling water on the radiator. That is followed by boilng water with my high quantity varsol gun. I can blow 1 gallon of boiling water out the end of the gun in about 1.5 minutes. It has remedied a lot of overheat problems for me. Simon C
On the quick visual, I was “getting the coolers clean” with air. But that was basically a false sense of hope. I was blowing dust through in some areas and not in others long ago. With the tube blower, I could see the jets coming through the coolant core and it was only coming through in some places and not in others, so when I blew it out with the air gun in the beginning, I was getting air through, but not everywhere. For the hydraulic core, I was getting NOTHING through. No water. No air. The dust I saw coming off of it was surface dust in the beginning. And like you said Nige, you can’t see anything so I was thinking I was cleaning, but I wasn’t doing jack. Plus, so much of the hydraulic core is covered, you can’t really get right on it and everywhere that was covered was a MESS. I have the cores completely clean now. Thankfully. I really feel like it was a combination of a lot of things going on. Hydraulics overheating and adding a large load to the engine, coolant not being efficient, and the AC adding more heat in front of the coolers with the condenser and the compressor added in that little extra load to the engine. I am going to try and get it out today and do some odd jobs around the house. It’s been a busy month running all over the place. But as stated, if this was the solution, it’s always something stupid and I thought I succeeded in blowing everything out, only to find that I was fooling myself because air was doing jack to those coolers. lol
The AC has its own issues at the moment. The charge is low, and the evaporator and drier need replaced so I can’t give it a full charge. So the AC isn’t proper but it “works” enough to make the components work and get hot. That repair is pretty low on the priority list right now because of the $1000 cost for those two parts.
The one thing that is obvious when mentioned, but which most people forget, is that fans are circular and radiators are mostly square/rectangular. So the corners of the cooling pack are never going to get as much air flow through them to assist with any self-cleaning of dust, and believe it or not but there isn’t much flow through the radiator in the centre right where the fan shaft is either.
Correct! It’s an often overlooked fact, and the radiator can only flow so much air through itself as well, and the corners and places that don’t get the strong pull of the fan will pack up easily, where as when they are clear they still move air, but not as much as where the fan is strong. So then you get warmer coolant towards the high flow areas since the corners aren’t “radiating” and then the center is slightly plugged or isn’t flowing properly and then it can’t cool properly. It’s a vicious cycle that just keeps things getting warmer and warmer. And unlike a vehicle running down the road, the only air crossing the coolers is pulled by the fan, so you don’t have that airflow generated by the speed of moving down the highway.