The Diesel Garage banner
1 - 12 of 12 Posts

·
TDG MAFIA
Joined
·
730 Posts
Discussion Starter · #1 ·
My truck has a toggle switch(not factory) mounted on the dash, the guy I bought it from said its to bypass the glow plugs. Why did he do that? Sometimes the truck wont start if you don't flip the switch and when it starts you put it back in the off position. Can I do away with this? and how so? Thanks guys

I just bought my first diesel yesterday. its 1985 F250 with a 6.9, the engine has a few leaks like the driver side valve cover, and the spout where you fill it up with oil the PO used silicone instead of using a gasket. The transmission pan needs a gasket. Its got a little rust on truck like the cab corners and has a hole in the floor, but nothing that cant be fabbed and fixed. ITs gonna be a project. Its got a little bit of rigging up but I will get it all fixed soon. Im just not use to all of the dang wiring yet, and dont know what everything goes to..
 

·
Grumpy Old Member
Joined
·
849 Posts
http://intellidog.com/dieselmann/glow2.jpg

Here you go.

Replaced the valve cover gaskets with the Fel-Pro rubber ones. The oil fill tube dosen't get a gasket just solicone. Clean it real good and use Ultra Gray solicone, I've used it for years and never had a leak, just dont get carried away with it.
 

·
Super Moderator
Joined
·
4,247 Posts
What happened is that instead of repairing the GP system by replacing (upgrading) the module and GPs to the newer style they rigged a by-pass that can easily destroy the GPs if not used very carefully and properly.

You have the older "12V" style GPs with male spade connectors, these are more tolerant of being left on too long if they are the OEM types, but not so much if they are aftermarkets.

Replacing the whole GP system will run you just over $200 in parts for the updated GP controller kit. It includes a new controller, complete wiring and 8 GPs. You can spend $80/year in GPs with a by-passed system, and have a lot more starting troubles than if they had just updated the system.
 

·
TDG MAFIA
Joined
·
730 Posts
Discussion Starter · #4 ·
so I should upgrade? Im not to familiar with the diesels yet but am mechanically inclined. What is it I need to buy to upgrade is there a kit? Also after I get that done what do I do with the switch? just remove the wiring to it do I need to replace it with something?

The guy said its got new glow plugs and return lines.

If it sits all day sometimes I gotts turn the bypass on even if the engine isnt warm
 

·
Super Moderator
Joined
·
4,247 Posts
There is a complete kit, includes everything you need to go from the old (slow) GP system to the newer modern FAST GP system.
 

·
Registered
Joined
·
349 Posts
John_G said:
Replacing the whole GP system will run you just over $200 in parts for the updated GP controller kit. It includes a new controller, complete wiring and 8 GPs. .
where can you get this upgrade kit?
 

·
TDG MAFIA
Joined
·
730 Posts
Discussion Starter · #7 ·
John_G said:
What happened is that instead of repairing the GP system by replacing (upgrading) the module and GPs to the newer style they rigged a by-pass that can easily destroy the GPs if not used very carefully and properly.

You have the older "12V" style GPs with male spade connectors, these are more tolerant of being left on too long if they are the OEM types, but not so much if they are aftermarkets.

Replacing the whole GP system will run you just over $200 in parts for the updated GP controller kit. It includes a new controller, complete wiring and 8 GPs. You can spend $80/year in GPs with a by-passed system, and have a lot more starting troubles than if they had just updated the system.

I remember the guy saying something about 6volt when I was talking to him, maybe he meant 12volt..


So when do I need to use the bypass?

I do have starting problems I have to usually hit the bypass button to get it started
 

·
Registered
Joined
·
349 Posts
The reason why you have to use the button is because the old diesel motors need the glow plugs to start or you will be cranking on it for a little bit. You can leave the button hooked up and use it like that, that's the way mine is hooked up right now. Just hold the button on for 8 seconds before the first start up then after the motors warm you don't need to use them to start. They do make 12volt glow plugs now instead of 6volts. You can get them at your local parts house. Whatever you do (DO NOT USE AUTOLITE GLOW PLUGS) they are junk and will end up costing you a lot of money down the road. I used them once and the tips of all 8 of them broke off and fell into the motor. I use ac delco glow plugs and haven't had any problems.
 

·
Super Moderator
Joined
·
4,247 Posts
Ryan,

The truck *may* already be converted from the old/slow 12V GPs to the newer/fast 6V type. It is EASY to tell for sure. Remove one GP connector, if it's round (bullet style) then it's the newer/fast 6V type; if the connector is flat (spade style) then you have the older/slow 12V type.

In either case, you are bypassing the control circuitry in the GP controller because something is not right with the system. Knowing which system you have (for sure) will go a long way towards finding the root cause of your problems.
 

·
TDG MAFIA
Joined
·
730 Posts
Discussion Starter · #10 ·
ok as soon as i can ill get out there and see what GP connector I have and get back with you. See the guy I bought the truck off of put in new Glow plugs and he told me about the bypass, but he said it was in there when he bought it.
 

·
TDG MAFIA
Joined
·
730 Posts
Discussion Starter · #11 ·
its been cold all night, went out and started the truck this morning and I had to hit the bypass, I guess it is to turn on the Glow plugs to warm it up right? Also after I got it started If i shut the gp switch off it died so I had to keep it on a few extra seconds like 10 seconds. But also I noticed the engine rattled a little bit when I started it u? what causes that? Thanks:shrug:
 

·
TDG MAFIA
Joined
·
730 Posts
Discussion Starter · #12 ·
John_G said:
Ryan,

The truck *may* already be converted from the old/slow 12V GPs to the newer/fast 6V type. It is EASY to tell for sure. Remove one GP connector, if it's round (bullet style) then it's the newer/fast 6V type; if the connector is flat (spade style) then you have the older/slow 12V type.

In either case, you are bypassing the control circuitry in the GP controller because something is not right with the system. Knowing which system you have (for sure) will go a long way towards finding the root cause of your problems.

They are flat. I am gonna try to attach an image of them to verify. So I need the new ones? Here is my assumtion on the glow plug by pass. Ive made a post about my ignition switch being bad, ya think that they got that switch there to run the GP's since they dont come on with the ignition switch? Because if I got the switch in the off position the truck wont come on and when you turn the switch on it will start right up...So where can I get the new 6v system at im wanting to buy as soon as possible. I got the money to get it and want to get it to get it right...

 
1 - 12 of 12 Posts
Top