4-71 DETROIT Engine

I have a tractor with a 4-71 Detroit that sits for long periods of time and takes awhile to start as I think the fuel has drained out of the system---just my thinking.
Anyway was thinking about installing an electric fuel pump to get the diesel fuel into the system for start up.
Would this work??? Where would I install it??? and would I keep it running--electric fuel pump--or shut it off once the tractor is running.
Thank you for any help.

And why not just install a one way check valve at the filters .

I expect you could do so but there is no guarantee that it will help.

Why not just start it every month or so?

Doing so is good for the battery(ies) amd other things.

Dean

Could you put in an electric shutoff like this? I've got them on three tractors to keep the gravity flow from the tank from flooding the carburetor. They should work the other way around.
Fuel shutoff

Where do you think it is draining out to. On the ground? Just tighten what ever fitting is leaking.

Detroit engines do require a check valve in inlet fuel line, unless gravity fed. most are locate3d @ tank. have seen them on filter. tank is best. if it has one it may not be working, maybe been taken off. I have used an electric pump to prime & start, but unhooked it after air worked out. that engine moves a lot of fluid @ 18-30+ psi. electric pump can't keep up imo.

Must be a injector nozzle leaking or something if the fuel drains back.
I had a old cat with a 4-71. one time it had been sitting for 10 years without being turned over once. It fired right up when i hit the start button. tank fuel level was well below the lift pump,..no check valve in the system.

NEW INFO. Well I plugged the old gal in and warmed it up and it took about 5 seconds for the tractor to be running. It had to roll over a few times. Maybe that is fast enough. I don't like to overwork those Big starters. First start in about 6 weeks.

What kind of tractor is it?

most of drain-back problems I have had is truck or equip with tank mounted quite a ways from engine & a bit downhill. fluid in line has enough weight to either pull air thru mechanical pump seal, or back up return. cure has been check valve in my case.

The 71 detroits don't like starting when cold. 12/71 was the worst. Always hated dealing with them on service calls. Starting fluid was useless. Had to get out the torch and heat the intake air.Until they started.

Every diesel I have ever had if it seems like it is losing prime then you start thinking about an injector pump rebuild.

I was able to limp a 3208 cat along for a while by installing a helper pump inline. I would flip that on and run it a while before cranking. It got to be where I had to leave it on full time or it wouldn't run. Then she died. Boy was that expensive.

As somebody asked. What is the ambient temperature when the 4-71 doesn't want to start?
All too often the two stroke is still crippled with the S series pistons/sleeves and the S series injectors.
You won't know it was the same machine with N series pistons/sleeves and C series injectors.
Also I've never seen a diesel engine yet equipped with too large of a starter, too large batteries or too large of battery cables.
If there is room for it. Delco-Remy makes a 44MT starter that along with a couple of group 31 batteries which will wail that engine over like it should be.

Now you got me thinking I never seen a cat with a
GM engine. Wondering if the canadian market did
have anything but caterpillar engines. I have
read that the alkian high way project in 1942 34
had some strange combinations due to the rush for
construction

forgot to ask Can you ship buffalo meat packed
in dry ice. Like to deal direct on merchandise
when possible. thanks bill

Oh now comes more info . You did not say anything about this about pluging it in . It's a Flippen Detroit IF and again i said IF it is in good condition and has NEVER had either fed to it and it under fifty degrees they will need a little cranking to get them to light . In the days of Detroits you had to learn each engines quarks . 1970 R 700 Mack with a 318 that had everything done to it to get a couple more pony's out of it to get it to start in the mornings on a cold day you had to pull the fuel stop and start cranking and crank her for fifteen twenty seconds the shove the stop in and keep on cranking and after twenty five to thirty seconds she would start to lite and you held the button down till ya had atleast three of the eight firing . A 4-71 in the old Lima 44 Crane would NOT start unless it was above sixty degrees with out either or a rag soaked in gas wrapped around the air cleaner . A 6-71 in a Modle C Le Tourneau Stared just fine down to 32 and it did not get run much maybe one a year for a couple weeks then it would set . Condition or the engine valve adjustment settings on the injectors and the condition of injectors mean a lot on how well they start You are working with and OLD engine not one of the newer engines of today and plus the fact that this is a two cycle verses a four cycle . The vary best cold start engines were the D 361 when they came out in 1963 as i have seen them start with out being pluged in or use of any either well down below 0 . My 1977 I H 4370 Eagle with a 350 small cam Cummins was one of the last to have a DE COMPRESSION release , and when it got down below 10 degrees you were tugging on the big TEE handle with one hand and pushing the starter with the other and you would crank it for a good thirty seconds before you let go on the decompression and hopped that she would light . even with four group 31 batterys you got two and maybe three trys before it was time for a recharge and jumper cables . So really i do not think that you are having a drain back problem as much as a LOW COMPRESSION problem or maybe a slow cranking speed problem due to a weak starter or to low of cranking amp batterys .

Hello lenray,

If you suspect that the fuel is draining back, a simple one way check valve will fix that. The check vale would be places between the fuel pump feed line and the tank. Cheap way to start the trouble shooting. Another easy thing to try, is adjusting the exhaust valves and the injectors. Late injection timing could be another reason it is not staring. Fuel pump pressure is another thing you can look at. Normal pressure is between 30 to 65 P.S.I.@1200 R.P M.'s. Is the air filter clean?



Guido.

"cat" is upper-midwestern for anything on tracks.

(quoted from post at 14:00:40 03/07/15) forgot to ask [b:a38c9bd847]Can you ship buffalo meat packed
in dry ice.[/b:a38c9bd847] Like to deal direct on merchandise
when possible. thanks bill

Click to expand...

es you can.
There is a few bison guys in the US that sell online and ship in ice.
Google is your friend.

My "cat" with the 4-71 was a Allis Chalmers HD-10.
ran like a charm, 13000+ hrs on it.
Allas,..i sold it

I don't have and experience with a 4-71. however, Where I work, They have electric fuel pumps on the Moffet forklift's we use at work. I think the older ones had perkins engines. I don't know if they are needed for everyday use, but they really help if you run it out of fuel.
Tim in OR

I think my 435 with the 2-53 has a check valve after the fuel filter??