So I've had this cat for about 2 + years now. Since I've purchased it, it's been a hard to start piece of equipment. Needless to say, battery got fried, replaced it with 750cca unit, all connections clean/tight no change. So I thought, maybe it'll be the starter. Such a nightmare to get at, I left it till the solenoid finaly packed it in. Replaced it, still no change. Always starts, just takes 5-8 seconds of steady cranking. Once warmed up, starts no problem. In our area, hardly ever gets below freezing, even in the winter. What do I look at next? Thank you.
try changing the injectors
Does it crank normally or is it sluggish when cranking? Have you tested the glow plugs?
You have to use the glow plugs when the engine is started cold. After it has some heat it should start fine.
Use the glow plugs. Hear the little buzz as they're heating up and wait till light goes off but haven't actualy tested them.
Ya might be the glow plugs. Do you have a block heater for it. Just a thought to try plugging it in to see if it starts easier. If it does id suspect either the glow plugs are burnt out or the relay/fuse or some times the harness itself. Ill talk with my buddy from cat this week and ill post ba k here.
Thank you everyone for all your replies/ideas. Looks like I will start with the glow plugs, and go from there.
Just a quick update on the above. So got the glow plugs tested, all checked out well. Made sure all contact points are clean. Just for the fun of it, one day decided to hook my truck up to the machine through the cables. Started like a dream. (Just seems like the starter is turning real slow.) So I went and bought another battery, with the highest CCA I could find that would fit in the box. Still no difference. Even if I cycle the plugs 2x and the temp outside being well above freezing, still 8-9 secs of steady cranking before she starts up. Once warm, starts good. Do you think it could be the injectors? Where would you go from here. (All related wires/cables) seem to be in good shape and tight. Still puzzled....
Try replacing the battery cables.
Does the starter motor crank over much faster when you connect the jumper cables..? If so you may have a parasitic load somewhere in the hydraulic system that is causing it to crank slowly. What grade of hydraulic oil are you using..? Also a thought. You say when the engine is stone cold it takes 5-8 seconds of cranking to get the motor to fire up. Have you tried cranking it for 3-4 seconds, then waiting say 10 seconds and then cranking it until it starts..? How long does it take to start the 2nd time you crank it..? If it starts after 3-4 seconds of cranking the 2nd time around (making 6-8 seconds cranking in total) I would be looking at the fuel lines right the way from the tank (and the tank itself - when was the last time the water and sediment was drained out of it?) to the injector pump. Maybe there is a small air leak on the suction side, maybe something as obscure as a small screen hidden inside a pipe fitting that is partially plugged - my vote would be for the air leak TBH.
Thank you. (and everyone else) guess the other thing to mention is once the machine has warmed up, even if it sits for an hour or two, starts quite well, maybe 3 turns.....
You said that after the machine is run for a while it'll start up nice there after... I would assume that is because all the fluids are warm and what not... When it's dead cold, could the fluids be so viscus that it is hard to start, such as cold hyd. oil moving through a pump perhaps?
Hence my question regarding what hydraulic oil it has in it, and while we're asking what grade of engine oil does it have in it..?
And while we're asking, On a cold windy day, if you shut it off for several hours will it start better than it will two days later at the same temperature? In addition to Nige's insightful crank timer suggestion, this will help tell if it's starting better because the fuel hasn't "drained back" or because the engine is warm and "limbered up".
Check the glow plug relay. Even though the plugs tested well they may not be activating to actually warm the cylinder heads...
Some more good ideas..... Thank you all. The hydraulic fluid is what ever is what ever the spec is. Our climate is very mild, hardly ever gets below freezing. For oil I run 15/40 rotella. Doesn't seem to make much difference whether it's in the 80's or 40's temp wise when starting. I've drained/cleaned the tank. last year, no difference. For fuel, I run shell brand. Yes, the starter motor turns over much faster and only takes about half the time for the machine to fire up. Yes, I have tried cranking 3-4 secs, let sit and do another round. no noticeable difference. I will try some of the other suggestions............
I have found that some diesels start with ease while others will be finicky, brand new or old. If it's giving the same type issue's on warm or cold days then I go through the fuel system, lines filters and all connections.
Sorry to sidetrack the thread, but if it's a hydraulic issue, the answer may be relevant. Nige, interesting that you mention the parasitic load. My new to me Komatsu PC50 MR-2 seems to suffer from this. On cold start, it will crank over 3-4 times sluggishly and then fire right up. Today I happened to notice that the boom moved just a little bit on start up. I honestly can't say which cylinder caused the movement. The safety lever must be up for the machine to start, so technically all hydraulics should be locked out. Where could a parasitic load stem from?
My 303 does the same thing. I changed the glow plug relay and the glow plugs that didn't help. Switched the engine oil to 5w-40 rotella synthetic, that didn't help. I also changed to a larger cca battery and that didn't help. I am going to try and switch to a thinner hydraulic oil and see if that helps. My next machine will be a bobcat.
I know this is an old thread - but incase someone else searches this, here's what I found on my hard starting 303.... I always thought the glow plugs came on with the key.... They don't. The kill switch/silver button is also the glow plug button... Push it for 10 sec before turning the key and.... it starts right up. Just thought I'd share my embarrassing discovery. (no, I don't have an OM for it).
If you want to get hold of an O&M they can be downloaded from the Cat Publications website as a pdf file for around $50, probably less than the cost of a tank of fuel.
Dan, where is this silver button located?
Location? Maybe post a pic of this "button"