Won’t go over 50ish

The place to discuss problems and routine maintenance questions and tips. This is for topics that are specifically diesel-related.
Kemmer1
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Location: Enderlin ND
Isuzu vehicle(s): 1982 2.2

Won’t go over 50ish

Postby Kemmer1 » Mon Jul 09, 2018 3:05 pm

I just bought a 1982 2.2 Chevy luv 4 speed, it’s in rough shape but Runs and drives good, only thing wrong is it won’t go over 50ish. Not sure what the problem is. But I have no clue about anything on these things but hope you guys can help or lead me in the right direction. Thanks a bunch.

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JoeIsuzu
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Isuzu vehicle(s): Original owner, '83 LS Diesel, 5-spd, 2wd, Long Bed, restoration in progress!

Re: Won’t go over 50ish

Postby JoeIsuzu » Mon Jul 09, 2018 4:23 pm

From what I've read, 65 mph is about all you should expect for the 4-speed 4x4 diesel. So you're not that far off from "normal".

As always, start with the easy (cheap) stuff. Do you know how long it's been since the fuel filter was replaced?

And unrelated, but REALLY important--
Do you know how long it's been since the timing belt was replaced?

If you plan to keep it a while, you'll learn a lot about it. ;)

Jack

Kemmer1
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Posts: 4
Joined: Mon Jul 09, 2018 6:26 am
Location: Enderlin ND
Isuzu vehicle(s): 1982 2.2

Re: Won’t go over 50ish

Postby Kemmer1 » Mon Jul 09, 2018 5:33 pm

I don’t not know either of those. A older gentleman had it sitting for awhile I believe and I just bought it from my friend that picked it up from him last week. So it’s probably been a while. But any other easy things I could look for?
Thanks for the help

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puttputtinpup
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Re: Won’t go over 50ish

Postby puttputtinpup » Mon Jul 09, 2018 10:04 pm

Yes, I 2nd changing the fuel filter. I always changed mine with the engine warmed up good. Have everything ready to go. When unscrewing the water in fuel sensor, get your channel locks up close to the filter as possible otherwise you may break the plastic sensor. Prefilled the filter with kerosene, diesel, or my fav, transmission fluid. Dont worry with pumping the primer. Fire it up a soon as you can. May stumble a bit but keep your foot in it. It'll clear up. For now, if the fuel lines aren't leaking, don't mess with them. Don't even take them off.
If changing the filter doesn't help with your top speed, click in the link in my signature and read the bulletins about power issues and cleaning the banjo bolts and screens. If it runs good after filter chg, i wouldn't mess with the screens and banjo bolts.

FiatSpider2
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Re: Won’t go over 50ish

Postby FiatSpider2 » Tue Jul 10, 2018 10:29 am

Ditto on the transmission fluid to fill the fuel filter. Use Dexron I or II and no higher and it will clean the IP along with the injectors and also help condition the o-rings and seals.
FiatSpider2 (4FB1 Isuzu Diesel powered 1978 Fiat Spider)