I just rebuilt my 7.3 (currently 386 miles) and installed 8 new MotorCraft glow plugs. It's getting into the thirties here in NE Wisconsin and the engine wasn't starting as it should. WTH? 6 of the 8 new glow plugs are dead. I.e completely open! I double checked this with my second multimeter, both are Fluke. Of course I tested everything else and it's fine. Any one else experience this?
6 out of 8 NEW Motorcraft GPs DEAD!
- Thread starter MeTo
- Start date
Bugman
Active member
Did you test the glow plugs themselves or through the valve cover harness?
If just through the harness I would pull the valve cover and test them with the wires disconnected.
If just through the harness I would pull the valve cover and test them with the wires disconnected.
I don't believe so since this is a fresh rebuild; I have been monitoring things pretty close. I can't rule that out with 100 percent certainty though. Not sure how long a burn out would take? It has been warm here, so starting hasn't been an issue until it cooled down recently. So I wasn't spending much time staring at the volt meter monitoring glow time. I don't pay much attention to the WTS light. The GPs were definitely new, no heat tinting. That can't be buffed or pickled out. I'm going to email Clay tomorrow and see what he has experienced? I will definitely be testing these before they go in.
Has anyone used gasket sealer on the VC gaskets? I'm thinking a nonhardening, not silicone. I noticed a slight weep in the back lower corner. I'm really trying to get this think oil tight.
Has anyone used gasket sealer on the VC gaskets? I'm thinking a nonhardening, not silicone. I noticed a slight weep in the back lower corner. I'm really trying to get this think oil tight.
Bugman
Active member
I am sure that you checked it but make sure that you have a glow plug relay and not a starter relay installed, if you replaced it.
There for a while Advance Auto was selling the starter relay and saying that it was for the glow plugs.
There for a while Advance Auto was selling the starter relay and saying that it was for the glow plugs.
rusty1161
Member
I had a little weeping going on, too. I took a straight edge to the valve cover and found that I tweaked it a bit the last time I installed it. Once I flattened it out with some pliers, no more leak. Might be worth checking.
Rusty
The new GPs are in. I compared the new set from Clay with the set I purchased from Amazon. NOT THE SAME! The Amazon GPS are 1.0 ohm and Clay's are 0.8 ohm. The GPS from Clay also have"Beru Germany 26A 0 100 226 138 11v" etched on each housing.
In conclusion, I don't believe the Amazon GPs are Motorcraft?
Would anyone have some laying around and check if anything is etched on yours?
In conclusion, I don't believe the Amazon GPs are Motorcraft?
Would anyone have some laying around and check if anything is etched on yours?
Garbage_Mechanic
Member
Speaking of the valve cover drip, I would not use sealant, I would find the fit up problem. My new engine came with a set of slightly beat up but not dented valve covers. I wanted to Linex them, so I spent some time making sure they were really flat.......They didn't look that bad but once I got into it they were about as bad as some old small block Chevy tin covers. Distorted at every bolt hole. We shall see when I get it running if I was successful. I'm a pretty good tinsmith.
For small nuisance leaks, I like to pressurize the crankcase with 1 or 2 psi of air pressure. Soapy water shows you everywhere the engine isn't air (and thus oil or oil vapor) tight. I will be doing it after final assembly and before drop in.
For small nuisance leaks, I like to pressurize the crankcase with 1 or 2 psi of air pressure. Soapy water shows you everywhere the engine isn't air (and thus oil or oil vapor) tight. I will be doing it after final assembly and before drop in.
^^^ This right here! I sure wish I had thought of that when my engine was still on the stand.
I took them off and trued them up. I was confident the o-ring in the vcg would seal. NO! The back corner still weeps. A little less, but it still does. I had enough and weather is getting cold here in NE Wisconsin. I put grey RTV on the valve cover and bolted them down. Over three hundred miles now and no leaks yet. I know it's going to be a bugger when I need to remove it. Futzing with the the leaks is worse IMO.
