[sdbrit68]

First off, thanks for the advice before from many, sorry I can't really contribute any knowledge to the forum, this truck is really my learning to be a back yard mechanic truck. I assure you, that when I have some know how, I intend to give back

I have a 1985 d250, 318 2bbl, automatic ( hopefully that is the important stuff)

When I got it, coming off the line it would kind of surge, didn't seem to have v8 power, but I contributed that to god knows if the engine has ever been rebuilt or how many miles are on it.

When I got up to, I believe 15 to 20 mph, it would take off some and act more normal with no surging. Uphill was crappy power. It took forever to warm up, when it did, the low speed surging would die down a little.

After two weeks I noticed, that when idling, the headlights would dim a little, but a rev of the engine would bring them right back up.

Left it sitting for a few days, and went to start it, nothing, but the headlights would come on dim, I pumped the gas pedal a few times and it started groaning, then fired up.

I have changed the fuel filter, as I have no clue if and when it was done, popped the caps on the battery, it was low. Put it on a trickle charger for a while, did the same thing, nothing, then pumped the gas pedal, groaned and started. Backed it out the driveway, to move cars around. Turned it off, then went to turn the key again, fired up no issues with needing to pump the pedal. ( I should state, whoever had it before me put a lexus battery in it, so, it could have been new, used, who knows)

I was also told it had a new voltage regulator, but he was pointing at what is to me an alternator, and it looks fairly new compared to the rest of the engine. I checked all the wires on it, the two red and green in the back the connections were loose, tightened them up, I have no clue what they go to. They have like very small canisters on the bottom of them with springs (n my haynes manual is not clear on it). I also cleaned the battery terminals. I will also state, there are connections which go nowhere, even though everything seems to work.

I had a minivan where the battery went bad, and it surged similar to this truck, only much worse. I was thinking car at first for the surging, but, it seems okay, but lack luster at speed.Which is why I changed the fuel filter. I was planning on runninga few cans of sea foam through the tank.

Checked the EGR , put my fingers underneath and didnt feel the movement that the haynes manual said I should have, and it looks old, was planning on replacing the PCV as it is cheap and dont know when it was done.

But, I am thinking electrical somewhere...any ideas ?

Please keep in mind, I am a neophyte, but willing to get dirty, I have a good ohm meter, but not schooled on using it other than to check fuses. I have already ashed my knuckles on it and bled on the engine, so it officially belongs to me now

 

[angusdevil]

Sounds liek the voltage regulator (or its ground) are going out. It'll be a small rectangle box (a little bigger than a deck of cards) on the fire wall with a weird shaped plug going to it. Unbolt it (2 bolts) and clean up the ground. Hell, add a small ground strap to it to make sure its grounded. Retest and see if that nets you any results. Those green and red wires you tightened down go to the voltage regulator.

When the truck is running, what voltage are you getting from the alternator? What does it read at the battery? Have you had the alternator tested to make sure its in good order? Most parts stores can check them for free if you bring it in. When was the last time you rebuilt the carb?

It sounds like a grocery list of small issues causing your problems.

 

[sdbrit68]

multi list is what I was worried it would be, honestly, the person I bought it off, said he replaced the car, but he is a tow truck driver, stated he used to be a certified mechanic, but seemed a little young for the full on ackground he was claiming.

Was thinking of running it down to the auto parts store to have the battery checked and alternator.

Thanks for the clue on the voltage regulator, I didnt see it pointed out in the haynes so going to go look for it

 

[angusdevil]

More specifically, they are on the back wall under the hood, a little to the passenger side. Can't miss it! VR's are items you want to make sure you get a quality one and not the cheapest thing that Vatozone has to offer. They're not too expensive either. I would start there and see where that takes you. Any vehicle that's that old will have issues. Some need fixing and others aren't all that bad.

 

[sdbrit68]

I bought it with the intention of rebuilding, the fact it runs at all was a huge bonus

 

[duval67]

I had the same issue. I'll bet on it being the voltage regulator as well. I cleaned up the ground on mine first, which solved the issue for a little while.
Couple days later, I couldn't get the truck to do anything more than click when turning the key, so I went out and bought a new voltage regulator. Put it on, boosted the truck (battery was completed dead), let the battery charge up, turned it off. Sure enough, she fired right up afterwards and has been perfect since.

 

[sdbrit68]

well, I am one for taking advice, going to kragens tomorrow to get one, the directions on finding it were spot on, and there were the green and red wires hanging out of it.

I think I am going to get a new battery too, just because this one is suspect, and I prefer good batteries

thanks, will let ya know how it works