Outer Limits 4x4 Board

hey guys im just wondering y the previous owner would bypass the glowplug timer unit and put in a pushbutton. any help would be appriecated.

Timer could be stuffed, easier and cheaper to have a hold in push button maybe?
A long time ago we had an old tractor with a push botton glowplug, you actually had to look through a sight glass to see a glow!

i seem to remember it was to dear to put new timer in my old mans 720 so they put in push button i think it's better someimes anyway just my thought!

yep, glow plug timer hangs on back of alt - expensive to fix/fit when replacing alt - so lots do without it.

Push button isnt required either, can hold ignition key on between "on" & "start" & hold glow plugs on manually that way. Works a treat.

Thats real interesting bit of info I'll keep that in mind next time i have trouble

How long does the timer normally run for?

It would probably be possible to find timers that would do the job as a cheap replacement but I am not a diesel man so I have no idea if it's 15 seconds or 15 minutes.

mines on first thing in the mornng for bout 10 seconds

patrollin wrote:yep, glow plug timer hangs on back of alt - expensive to fix/fit when replacing alt - so lots do without it.

Push button isnt required either, can hold ignition key on between "on" & "start" & hold glow plugs on manually that way. Works a treat.

That's the vacuum pump on the back of the alternator. Glow plug relay/timer is still expensive to replace though, but easier to get at

My timer still works, but doesn't glow long enough to start the engine (low compression ) so I just turn the key half way from IGN to START until i hear the click of the relay, and hold it there for another 10 seconds before starting.

re: making your own, it would be simple to get a little microcontroller to turn a relay on for a time dependent on engine/air temperatures, and it'd still be cheaper than a nissan one.

festy wrote:

patrollin wrote:yep, glow plug timer hangs on back of alt - expensive to fix/fit when replacing alt - so lots do without it.

Push button isnt required either, can hold ignition key on between "on" & "start" & hold glow plugs on manually that way. Works a treat.

That's the vacuum pump on the back of the alternator. Glow plug relay/timer is still expensive to replace though, but easier to get at

My timer still works, but doesn't glow long enough to start the engine (low compression ) so I just turn the key half way from IGN to START until i hear the click of the relay, and hold it there for another 10 seconds before starting.

re: making your own, it would be simple to get a little microcontroller to turn a relay on for a time dependent on engine/air temperatures, and it'd still be cheaper than a nissan one.

yes of cause - being readin 2 much bout vacuum pump lately
timer unit hangs off side panel behind passenger side headlight (forward of battery). - did I at least get that bit rite???

patrollin wrote: yes of cause - being readin 2 much bout vacuum pump lately
timer unit hangs off side panel behind passenger side headlight (forward of battery). - did I at least get that bit rite???

yes and no
The glow plug relay is behind the driver's side headlight, under the black bracket that covers the injection pump controller. The actual glow plug timer/control box is the gray box just underneath the fuse box near the driver's feet - at least that's where they are on MKs.
I'm pretty sure it's usually the control box that fails, not the actual relay itself.

The box in front of the battery on the passengers side is the external voltage regulator for the alternator, a Hitachi mechanical unit that is crap and doesn't seem to have a direct aftermarket replacement available.
Luckily, a very common $40 electronic regulator can be fitted by swapping a few wires around.

festy wrote:

patrollin wrote: yes of cause - being readin 2 much bout vacuum pump lately
timer unit hangs off side panel behind passenger side headlight (forward of battery). - did I at least get that bit rite???

yes and no
The glow plug relay is behind the driver's side headlight, under the black bracket that covers the injection pump controller. The actual glow plug timer/control box is the gray box just underneath the fuse box near the driver's feet - at least that's where they are on MKs.
I'm pretty sure it's usually the control box that fails, not the actual relay itself.

The box in front of the battery on the passengers side is the external voltage regulator for the alternator, a Hitachi mechanical unit that is crap and doesn't seem to have a direct aftermarket replacement available.
Luckily, a very common $40 electronic regulator can be fitted by swapping a few wires around.

amazing, only sold the MQ this Feb, after 15 years ownership, & already forgotten where everything is (was)!!!!!!! To be far though, actually never had any probs with any of these things (glowplug timer never existed when I brought it), so never had to play or fix these things.

thanks for setting us all straight - it is handy to know about these things, especially with vehicles approaching 27 years in age (like my old girl - 10/1980).

I did some reading on how the glow plug timers operate and now I realize that mine isn't working properly

They only have 2 inputs, engine coolant temperature, and alternator output. The alternator voltage sense is just to cancel the glowplug timer as soon as the engine starts.
The glow time apparently should be ~35 seconds with coolant @ 10 deg c, to ~8 seconds @ 80 deg c. Mine only ever glows for <10 seconds.
I'll test my temperature sensor and connections to the timer unit, but otherwise will make my own replacement one.

I find if i turn the key to far to start and let the key go back to on the glow plugs don't glow so i have to turn the key off and let it sit for a few minutes to reset the time it's a pain in the arse. so maybe my timer is on the way out, might pull the cover off and have a look.