Hard start

SHADE-TREE-MECH

MEMBER
1991 FORD E-SERIES VAN

Diesel 7.3 L is starting hard. When engine is cold (not-
run-for-over-eight-hours) it starts up right away,
BUT ONLY RUNS FOR 3 SECONDS AND STALLS.

It can't be the glo-plugs, because it does start right up on the first try. But after it stalls, I have to crank for about 45 to 50 seconds before it will start. Lots of blue smoke after it starts, but being a diesel, can't tell if that is normal.
Runs just fine after it does start.

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

If you have a long crank on diesel then we need to rule out fuel and compression first and foremost.

Here are a couple guides that will help with this issue and the tests that we need to run to start.

https://www.2carpros.com/articles/engine-cranks-excessively-before-starting

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

https://www.2carpros.com/articles/how-to-test-engine-compression

Once we know what the fuel pressure is and what the compression is then we will have a better idea what this could be.

Basically, we are looking at injection timing or just a damaged engine with low compression.

The blue smoke tells me that we are getting a build up of oil and fuel due to the excessive cranking so we may have a bit of blow by which should show up in the compression tests.

Please run through this testing and let us know what you find with. Thanks

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