Hey guys,

I just changed the head gasket and had the heads machined on my 1996 Jeep Cherokee. I've put everything back together and now it won't start. It is turning over, but it sounds like its not getting a spark or fuel? This is my first time doing any work like this and wondering if anyone has some advice for troubleshooting and trying to get this started now.

Thanks,

Kevin

 

To check if there is spark, all you need is a working plug connected to a plug wire and a helper to crank the engine while you watch it.

One way to get fuel in is by spraying carburetor cleaner to the intake while someone is cranking the engine and it should fire.

Better be careful not to overdo it and get burned!

🔥

 

Did you remove the distributor as part of the replacement? Usually the problem folks seem to have after doing major engine work is a mis-indexed distributor.

 

Thank you. I currently don't have a buddy to help me crank it until tomorrow. I've heard I can cross over the solenoid on the starter with a screwdriver and do it myself but seems a little risky. Any way to check if the engines getting fuel?

 

I didn't do the distributor and labeled all the plugs. I didn't take the plugs out of the block when it was being machined and used the ones from before the rebuild (they were only a month old), could this be a problem?

 

* Do not try to jump the starter with a screwdriver.
* Check and double check all wiring to make sure a connector did not get missed, a connector is not fully seated or that something did not get damaged during removal/install. Make sure nothing got pinched at the firewall end of the head.
* Verify crank position sensor (at top of bell housing) wires are OK and that the sensor is not damaged. A faulty crank position sensor will result in a no start. A resistance check can help verify it is not open/shorted.
* verify the ground strap from the driver’s side rear head bolt to firewall is connected and in good condition. Check with an ohm meter - resistance should be almost zero.
* Some years have a Schrader valve (looks like a tire valve) on the fuel rail to release pressure. You can use that to verify that you have fuel to that point.
* Verify that the manifolds are flush with the head. Did the manifolds get seated properly on the dowel pins. A gap on the intake manifold might upset the air/fuel ratio enough to prevent a start.

* Plugs are not the likely problem unless they were contaminated with metal or oil. I suggest pulling and cleaning each.

 

Grounds, grounds, grounds! Make sure ALL your ground wires are installed and clean/tight.

 

* the '96 has a valve on the fuel rail, which can be used to check if fuel is pressurised

* to test spark with no assistant, take out a spark plug, connect it and lay it on the engine,,,it must be earthed (where u can see it from outside the car), reach in and crank the motor, do it near sunset or dark, and u can see (or not the spark plug firing)

* dont short the starter if it already turns over ok

 

What did you find out??

 

Yes, if they were not inspected for damage & cleaned out afterwards!