Read through what I could find on here about this engine but it was old so I started a new thread. I got a call today to check out a 315 for no start, I am second to this as the dealer put a starter and battery in it and told customer it was not worth fixing... The machine has 487 hours on it and is in great shape, it just never gets used. I confirmed interlock circuit and fuel shut off is functioning electrically. I bled fuel system with vacuum pump and while cranking have fuel pumping from return to tank. Cranks strong and is pushing a decent amount of black smoke, it will NOT pop off on a small amount of ether.... and sounds like it briefly vapor locks. This is only the second one of these I have touched and the other was a bad fuel shut off solenoid. It was end of day so I ran out of time, but plan to return and pull rocker cover to inspect/bleed unit injectors. I am also going to drain fuel as some water was noticed. I do not know if the aneroid system could be effecting the rack position or something? Any advice is greatly appreciated. Thanks The initial complaint from customer was progressively harder starting until it would no longer start. Machine serial is T00315A153104
Wonder if it will fire with WD40 being blasted into the air intake while cranking. Oil improves compression greatly, if it fires right away when doing that the cylinders or head are suspect of being in not so good shape. Maybe it is a fuel rack problem, but maybe cylinders are scuffed a little or glazed smooth with no oil retention. Worth a try. Simon C
Welcome to HEF Align ! There are so many thing's that could be causing this. Let's start with the basics, plus a couple of other items to check. Did you measure fuel pressure? If so, does it hold 4 psi for at least 15 minutes after you stop cranking? Did you try to pinch the fuel return line off to see if it starts (don't let it run like this)? Has the glow plug circuit been checked (another reason ether shouldn't be used)? Cranking speed good? On those engine's, using ether tends to bend pushrods and/or cause camshaft gear slippage, causing even more diagnostic confusion. So the pushrods will need to be checked. Camshaft timing requires very special tools to check, so we'll table that one for now. While the rocker cover is off for pushrod inspection, look for broken injection pump springs with a mirror and a flashlight. While the rocker cover is off look at the intake ports. Signs of dusting? Remove the little cover from the front of the timing gear cover. Activate the fuel shutoff solenoid. Measure the total fuel rack travel. It helps to have a metric steel ruler cut in half to make it shorter so it fits. Total rack travel should be 21.5 mm. If it is not, then the magnet fell out jamming the rack. With black smoke while cranking, it could also have a leaking injector. But that would require both the pump and injection pump assembly (they are a set and not sold separately).
SELL SELL SELL!!!!!!
Engine cranks strong to 320RPM, confirmed on display while cranking. Did not pinch fuel line but did pull a slight vacuum on return while cranking and had fuel. Ether was barely used, I understand it's constraints.. It was used to test for pop off. I do not know if it has been used in the past tho. Glow plug circuit is functioning through relay and into head. I confirmed fuel shut off is pulling but did not get to pulling the cover and inspecting linkage. My plan was to inspect injection pump springs and rack position, thank you for the specs. I have the machine manual but could not find a decent 4025TT engine manual. I plan on returning next week. Cheers and thank you
Engine manual needed for that machine is CTM301 (2.4 and 3.0 Liter). Pulling a vacuum on the return line will not show a faulty return line check which controls the fuel pressure.
Heading back tomorrow morning, snow delayed my visit. Will report back.
Ok, I'm here now. Pinching return did not help. I pulled front fuel rack cover and it seems the rack is moving... Radiator so close had to get a accurate measurement. There is a lever that the fuel shut off his banging and staying in one position, but I can move it back to neutral? The magnet seems to be there as I saw it with my bore scope. Any other checks before I pull manifold? Thanks
Pulled intake, no broken springs on pumping units. I can see the rack moving in block, it doesn't seem it's moving as much as the shut off solenoid is moving at the cover end? No bent push rods either....
In your post #1 you state that it will not pop off with sniff of ether. Need to try with WD40 as I posted. If it doesnt fire you will have to pull head to see if broken rings or something. You stated that glow plugs work. None are burnt and all are drawing current(4-10 amps each dependant on the style). You either have no fuel or no compression. Simon C
Forgot to follow up, the engine has low compression. Customer does not want to fix... Going to auction.
Exactly like I thought. If it won't fire with oil, cylinder condition is a first check. Someone will bye for spare parts. Simon C