The Classic Machinery Network

Hi, I'm running a British leyland 98mm six cylinder and though the engine starts and runs fine it seems to be using much more fuel than the previous own told me Iit would and it always has black smoke visible. It also seems to be short on power, though I don't know the rating on my engine as the markings on the block are not listed in the operating manual that came with it.

I was wondering if adding a small amount of boost would clear up these problems?

If it is blowing black smoke it has un burnt fuel going straight thru maybe the aircleaner is restricting it to much I have had one of these motors in a tractor and they are good on fuel and start and run spot on and run nice and clean as well
they came in 2 power ratings in tractors 85 and 100 hp I think the truck motors turbo charged were 150 hp but not sure maybe only 125 hp

Paul

Run it out of dusty area minus the cleaner and see if it make any difference. Next port of call might be to check the pump timing which should not really be wrong if nothing touched. After that the injectors.

Brand new air filter, antifreeze, fuel filters, and oil. It's got less than 25000kms on it from what I can tell.

to be honest I'm not sure how old the engine is. Some old farmer had a shop in Winnipeg Manitoba Canada yank out the factory Chevy 454 and graft in the BL, and in doing so he went from 7 mpg to 17 mpg according to the documentation I got with the camper. The really strange part is though, instead of an auto he opted for a 5 speed standard! with all that said my understanding is the guys doing the conversion were BL dealers so one would think it wasn't a used engine. So if the timing is out you'd almost think it's from factory....and in the hole it's in it isn't going to be easy. Any good rreference materials for checking it?

Before you get ripping things apart; check the air intake is not restricted in any way; also check fuel sediment traps and the quality of the fuel itself (that there is no muck in it)
If the engine has a turbo you should check that too simply remove the air intake where it joins the turbo and check that you cannot move the turbine up and down, if you can then you have a knackered turbo which will give you all the symptoms that you have described.

Jeremy

Jeremy Rowland wrote:Before you get ripping things apart; check the air intake is not restricted in any way; also check fuel sediment traps and the quality of the fuel itself (that there is no muck in it)
If the engine has a turbo you should check that too simply remove the air intake where it joins the turbo and check that you cannot move the turbine up and down, if you can then you have a knackered turbo which will give you all the symptoms that you have described.

Jeremy

Could the pipe from the air cleaner be collapsing?

It's non turbo, and no visible problems with the intake tubing and piping.

Another suggestion would be to check the fuel lift pump is correctly working and check that there is no restriction of fuel from the tank to the lift pump; a simple gravity feed can rule out these possible issues.
If the lift pump is okay and there is no fuel restriction I would be taking a look at the fuel injection pump itself; the timing is highly unlikely to be out because the engine would probably not run if that was the case, also look at the fuel injectors.
I know this sounds like a daft idea but stranger things have been known; what is this engine powering because all the symptoms you describe can be accounted for by sticking brakes; lack of power, black smoke as the engine struggles to cope with the added load and greater fuel consumption?

Jeremy

It powering an 84 GMC workhorse chassis with an 84.5 Triple E class A motor home on it. I've just had all the wheels in the air and they turn reasonably freely by hand, now anyway. All the brakes are straight hydraulic with hydraulic assist and the right front had a collapsed brake hose that acted like a check valve and that corner would drag badly. But all that was fixed before I drove it more than about 10 miles when I bought it.

I'll try testing the lift pump though, does anyone know the recommended pressure and flow rate?

The Bathgate engine in Tractor format was in 3 styles N.T.-D.T. and T.T. with a fuel system setup for Tractor spec' the Truck engines had differing spec fuel injection and parts fitted, the black smoke following you about could be caused by a Thermo-Start fitting located in the inlet manifold that is faulty? a Tractor engine is no use in a Truck and a Truck engine is not much cop in a Tractor, I would think this engine is a re-power in your GMC and possibly lacking on the "Beans" to poke it along, a few pictures of the engine including the Serial No off it also the weight of the thing its dragging along would be handy, as already said the injectors might be in need of new tips, also the inlet valves are pegged as they are shrouded so don't rotate (Woodruff Key locked in guide) and are known to need fettling some.
tctractors