LUVTruck.com

Hi to all you luv people out there . I am a new luv owner 1980 stepside . I am quite capable mechanically but figure that with the combined experience of the site ,someone can give me the quick fix.
I have no electricity going to the balast resistor [ceramic block next to coil] and no fuel or temp guage working . I can hot wire to balast and car runs fine ,I checked ign.switch ,it's good . Any ideas ??? before I check everything out . Thank for any help Jim

This has happened to me even though the fuses were good.

The problem was corrosion on the blad connectors in the fuse block.

DISCONNECT YOUR BATTERY

Remove the fuse block phillips screws and one by one take the connectors off, and clean them with solvents and fine sandpaper or a wire brush. Should work OK.

The power to the resistor comes through those relays under the metal cover right behind the coil on the fender. You could also have a charging issue as the alternator is the trigger for those relays. Of course contacts at the fuse block are also a problem and well worth the time to clean up. I also put a little "bulb grease" on mine the last time I cleaned it to keep it from getting crudded up again. Seems to be working well.

Check for charge from the alt, and then start looking at the relays. One is for the resistor bypass (runs 12v straight to the coil when key is at start) and the other controls the fuel pump so it cuts off if the motor dies. They are tied together though. On the main luvtruck.com site there are wiring diagrams that should help you troubleshoot the wiring.

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95 Isuzu Trooper Daily Driver
86 Isuzu Trooper reliable backup
77 LUV 2wd stock beltway blaster (resting)
79 4x4 LUV project: 2.6L, 5spd, 31s (eventually)

MEPR: Man, my 4x4 makes all other LUVs look good

Hey thanks for the replies guys , I had checked the fuse box connectors [all good ] but I did find one fuse unblown but no good , changed it and the car runs off the key normaly , But now I am not getting gas , so when I get a chance I will check pump relays and filters [the truck sat for 6 years so I may have sucked up some crud .
The temp guage now works but reads max hot all the time ,so it must be grounded , where is the temp sender located , is it on the bottom of the block pass side further back from the oil sender ? .
fuel guage still not working , but time will cure all the problems.
Thanks Jim

If your truck is not charging the fuel pump relay wont energize.

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Certified pilots, looking down on people since 1903.

The temp sender is on the bottom of the intake. If you feel around almost directly under the thermostat housing you should find it. It feels almost like a bolt but the head is more like a nail. The wire is I believe black with a yellow stripe and the connector slides on to the "nail head" from the side. The wire should come out of the harness from the area around and in front of the coil kind of with the wire to the distributor.

The fuel pump only runs when the key is on start or when the key is on and the motor is running. (assuming the alt is charging and kicking on the pump relay). If you prime the carb with a full fuel bowl of gas it should run for a minute or so, long enough to get it started and then put your hand on the pump to feel if it is working. I don't doubt you have crud in the filter and tank but if you can at least verify you've gotten the electrical gremlins out of the way that will help.

The pump (if still stock style) has a filter inside it. One end has a bolt head on it and twists off to reveal the filter. Replacements are hard to find, but even just blowing that out with an air hose should get some flow restored if that is the culprit. I JC Whitney sell a similar pump and had the filter for it. The pump is overpriced but the filter and gasket kit is about $10. I have not verified that this fits the LUV pump exactly, but here is the link:

Filter and gasket kit

Fuel pump

You can see from the picture of the pump if yours is like it or not. The only difference I see is that the stock LUV pump has different fittings for the hoses going in/out.

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95 Isuzu Trooper Daily Driver
86 Isuzu Trooper reliable backup
77 LUV 2wd stock beltway blaster (resting)
79 4x4 LUV project: 2.6L, 5spd, 31s (eventually)

MEPR: Man, my 4x4 makes all other LUVs look good

There is a trick to find that Luv fuel pump filter. If you ask for one for the Luv they may say their book dosen't list one. Just ask for one for a Datsun 240Z, same thing, used the same pump those years.

Thanks for all the replies. Today I primed the carb and it ran fine . The fuel line was clear but the pump is not pumping , I will check that tomorrow . there is a special place in hell for the engineer who said lets put the temp sender unit under the manifold a little too much saki that day . What is the thing that looks like a sender unit that sits level with the oil sender but farther back on the engine towards the bell housing.It has 2 wires coming off it [mine are cut ]and I see no matching wires near them .Thanks again guys Jim

Hi guys today I checked fuel pump it works but gets no electricity , does anyone know a way of checking the relays to see if they're good ,are there any querky problems they have . My workshop manual arrived today , but does not say which series mine is 1980 california model ;from the years and simple deduction it looks like a series 10 ??? can anyone help ???
one piece of info I can help with is on the carb , I hear people commenting on the carb being problematic. I had the same carb on my old courier [loved that truck ] and from time ti time it would only run on the vacum secondary circuit ,[it would run bad then in the mornin fine ,so called experts told me the problem was distributor fuel pump and everything else . I found that upon very close examination that the wieght that sits in the primary circuit had over time gauled the aliminium housing , so usine a dremel q tip and polishing compound I polished it out and polished and debured the wieght and hey presto it ran perfect and never gave a problem Jim

If you pull the relays there is a way of testing them but I would bet that is not your problem. Your truck must be charging for the fuel pump to energize. Prime it and get it running to see if it is charging first.

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Certified pilots, looking down on people since 1903.

Grumble Grumble Grumble Today I checked the wires and someone had used a crimp commector on the fuel pump lines and it had coroded inside so I replaced the wire ,which was undesized and current is now fine , I even back tested it and made the starter turn , But now the fuel pump is not working , I bench tested it and it's dead , I think it was on its last legs and me putting current to it on a good heavy wire finished it , with the old thin and intermittant wire it was sputtering along enough to idle [it was running rough ] so tommorow in goes a new pump Thanks for all the help guts Jim

'78 is a series 8, so it makes sense that an '80 would be a 10. Assume you have an electric fuel pump, the diaphram dries out if they aren't used for a long time. I got a generic from Autozone, works fine, just had to drill a new mounting hole. I think Rockauto has the factory style, about the same price.

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'78 Chevy LUV,1.9,4sp,headers,31's,SAS Dana 30,Dana 20,SOA rear w/Aussie Locker, rough body, bought new 12/4/78.
'87 Trooper,2.3,5sp,headers,31's,ball joint flip & spacer,Aussie Locker rear,Superwinch hubs,brush guard w/5.5K winch,more to come.

Yeh new pump goes on tomorrow and it must be a series 10 Thanks jim

Hi guys well the new fuel pump is on ,I did a nice job if I say so myself , new hoses clamps and heater hose slid on the outside of the fuel line for chaffing . It started right up I drove it down the street and it flooded out . I will check it out tomorrow but ,does anyone know if the vehicle should have a low pressure pump ?? it had a universal unit which I replaced with the same one rated 5.5-9 lbs pressure . Is it pushing past the valve seat ,maybe I need to drop the float level to put more pressure on the valve seat . its hard to know as the old pump was faulty . what are your words of wisdom.

It's probably not pushing past the float. The fuel pressure you listed is normal operating pressure for the hitachi carb. The float could be stuck open from old fuel residue all over the inside of carb. If thats the case you should have the carb rebuilt. If you think that you can do it there is a big container of carb cleaner sold at your local NAPA store. It allows you to soak the carb pieces in that cleaner. (Comes with basket) You will need to buy gloves. The stuff is very corrosive, but your carb will be very very clean. Hope this helps.
Mike.

hey thanks mike I was thinking [yes it hurts] That as the carb sat empty for a couple of days maybe the float is stuck open . when a carb never goes empty ,over time the crud builds up above and below the normal range of movement so if the float goes wide open the crud sticks it open sometimes . I have taken that type of carb apart many times and know how to make it run nicely , so tomorrow it's war . Jim

Fuel pressure should be 3-4lbs.