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80 Toy 4wd truck 20R running problem...

Hi all! i am new to this group and I hope you can help me... I am the

2nd owner of an entirely original 4wd 80 Toyota truck longbed that onlyhas 125K orig. miles.. It is completely stock. I just went through a lot of cleaning and a fresh tune was in order... New belts hoses, plugs Toyota wires, cap rotor and I set the timing to 8 degrees before TDC. It has all new filters including gas... New radiator , thermostat and alternator/battery. It passes California smog so cleanly that the smog guy thought I was trying to hide something... It does not smoke OR burn any oil... IT has a 5 speed in place of the original 4 speed.

Heres the problem:

It will start fine and run fine when its cold and when it warms up.. NO problems... Wake up in the morning and drive away... No problems.

Lets say I go to the supermarket after driving it for about 30 minutes... I stay in the market for about 30 minutes and then come out.

The truck will start but immediatly die.. OR it will take a LOT of pumping of the gas to get it started and then it will die immediatly

IF I keep my foot on the gas it will run but poorly, missing and hesitating, bucking etc.. FOR ABOUT 3-4 MINUTES OF DRIVING.... it will stall if I let off the gas.

After those 3-4 minutes of driving, it will drive FINE. no problems idling and drives nice and smooth...

It has excellent oil pressure and it never runs past 1/4 - 3/8 on the temp gauge

Your suggestions? I love this truck and really wish that will run better...

Also what do you think of a 22R carb to replace this one? DO the conversion kits work well? Better fuel mileage?

Thanks alot folks! I really appreciate it. I am happy to be part of this group!..

Pete

Reply to
80toy4wd
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  1. Do you have the Haynes manual with the troubleshooting section for this vehicle? Oftimes that helps a lot faster than we can.

Double check the vacuum advance hoses to make sure they aren't kinked or something isn't in them.

Do you smell any gas when you're having to hold the accellerator down or when it's running rough?

Charles of Kankakee

Reply to
n5hsr

Vaccuum hoses are like new and all of them are connected. No I dont smell gas although I am suspect that its reall sensitive to flooding easily.. So it might be a happy medium of pumping the gas when starting it... I am not sure if its flooding or starving... No obvious smell of gas though.. Thanks

Reply to
80toy4wd

The condition is referred to as a "hot soak hard start." That is, get the engine good and hot, then while it is sitting for about a half hour, it is soaking up all the heat generated by the engine, exhaust, etc.

When you start a cold engine, you depress the pedal all the way to the floor to set the automatic choke. Try giving pressing the gas pedal only halfway when starting a hot or warm engine to see if that helps.

Look at the fuel level in the carberetor bowl - there is a sight glass on the side of the car with notches halfway up the window. The fuel level should be right at the notches.

Make sure the heat shield is in place over the exhaust manifold. If it is missing, the heat from the manifold can evaoprate the gas in the carb. The heat shield should have louvers on it. If it doesn't, then have the truck checked for the exhaust manifold special service campaign.

Check to make sure the air filter element isn't black with soot. If it is, the exhaust manifold may be cracked.

Sorry, no experience with conversions.

Reply to
Ray O

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