Glow Plug Relay Shot - Bypass ??
 

No start today. Perfect Storm. Oil's too thick, no Powerservice in the fuel, GP relay is intermittent at best, quick drain on the battery. I had an appointment today to get the beast to my mechanic for an unrelated matter and I couldn't make it. Now I'm stranded. Is there any way that I can bypass the GP relay to get the sticks to do their thing? I don't want to start any fires, but if I could glow manually that would be awesome. Assistance Please!

Sure you can.

Get yourself some 12 guage wire and cut five pieces about 12" long. Strip off both ends. Twist the five wires together on one end. Remove the plug from the side of the glow plug relay. Insert one wire into each of the five sockets.

Carefully attach a jumper cable from the + battery terminal to the twisted group of five wires (don't let it hit the body!!).

Wait exactly 30 seconds.

Start the engine.

Remove the jumper cable and the jumper wires. Replug the relay.

Elegant solution. Thanks.
I'll let you know how it works.

T

I already know how it works..........:eek:

:o

Contact!
 

Thanks Brian.
I'm not sure that the gp's are supposed to get 12 straight volts but it totally got me over the hump. You rock.
Word!

Anytime.

Yep, 12V is preferred on them..........if you want to start it...........that is.;)

They normally get about 11V, but I'm sure the direct 12V won't hurt them.

Since the plugs get current from the heavy wire attached to the 80 amp fuse, I believe instead of jumping it to the battery, you could just touch the twisted end of the 5 wires to one of the screws holding the 80 amp fuse.

I bypassed the non-functioning glow plug relay on my 6 cylinder 82 Volvo D24 diesel back around 1995. I used a remote starter solenoid to take the place of the relay and have a push button switch mounted in the dashboard. If the glow plugs are not supposed to get 12 volts it has not caused a major problem for me. Over the years I maybe average changing 1 plug per year. The most I have had fail at 1 time is 2. However, I do not live in a cold area it seldom gets below 40 where I am.

the reason they normally get 11 volts, is due to the FACT that the battery can't put out 70 amps of load at 12v, it's the battery that drops the voltage, not the relay. you're not giving direct 12 v. you are giving it all the battery can put out. get a volt meter on the battery itself, and measure the volts as the GP's are energized. I bet the battery drops to 11 or lower v... have fun!
and don't question Brian's wisdom

Very true, but there may be additional voltage drop through the relay than through a direct wire. If you jump start a car from another running car, the GPs may see 13V. In amy event, it's not a problem for the GPs. I was just pointing out the the GPs are rated for 11V (i.e., they will perform their function if they gat 11V).

I see it every morning on my volt gauge, it falls to about 10.5-11volts when glowing, jumps between 10 and 11 when cranking, up to around 12 when running with afterglow, and then rises back up to 14.4 after the afterglow system shuts down. Someday I will try to switch to a bigger alternator....so it can handle the load of the afterglow without putting any draw on the battery....even so, the load is minimal....perhaps 5-10A for a few mins at most...less than leaving the headlights/other lights on for a few mins. So I doubt it has any negative effect on the battery.

Which of your vehicles has afterglow, and how did it get it?

My '82 300SD has had it for about 3 years, I bought the kit and installed it, its a great upgrade.

We just replaced the original (ailing) relay and original (half dead) glow plugs on my dad's 300D with the afterglow system as well, huuuge improvement. Starts smooth and instant now, before it was very cranky *pun!* :D about starting when it was below 40 outside. Now it fires off smoothly in one crank at 10F!!

Which one of your vehicles did you want it for? I don't mind doing an internet search of parts dealers. I believe I saw one 2 days ago for 82 or 84 300D $99 relay + 4 glow plugs if you wanted the 5th glow plug it was extra.