OVERHEATED 98 tacoma V6 4X4..what do I do next?

[mark P.]

This summer I had a leaking waterpump and like an idiot I didnt repair it in time. As a result the truck overheated on the highway and is now parked in my side yard. The local repair shop said I need to replace the engine or rebuild it. They said that when they tested the cylinder compression, it was only putting out about 60% in two of the cylinders. Radiator is cracked also..... I was quoted around $3000 for engine rebuild and radiator, out the door.

Is there a possibility that maybe its just the cylinder heads that have cracked and if so would it still require a major engine rebuild or could these guys be just jacking up the costs for more business?

I probably should take it somewhere else for a second opinion...but that cost $$$ too.

Any recommeded shops in Phoenix/ Gilbert area to take a look at my truck?

Last question.... any advantages or disadvantages when deciding to rebuild my current engine or just buy one already rebuilt? Would prefer to keep my own, although it has 245,000 miles on it. Great taco until now!

any advice is appreciated.

Mark P.
Gilbert, Arizona

 

[tbplus10]

Hey Mark:
The 3.4 isnt a very forgiving engine when overheated, your problem is probably the heads or head gaskets, at this point Id recomend pulling the heads and having a shop check them for cracks, if their good have them checked for warping and check the valves.
If everything turns out good then put on a new water pump, radiator, and change the timing belt while your that far in.
Flush the engine, heater, and radiator/hoses.
Put it all together and give it a try.
If the heads are cracked, which is a real possibility with 3.4 heads, get the engine looked over for cracks and if it checks out ok find a replacement set of heads.
Youll probably have an easier time finding a whole engine over just heads, keep in mind some Toyota sedans share engine parts with trucks, so while you might not be able to use the whole engine due to it being a side sitting engine you could use parts like the heads.

 

[mark P.]

Thanks Tbplus. I will pull the heads out and take them to a shop. Sure sounds cheaper than a total rebuild, if thats the only issue.

 

[tbplus10]

The block is durable and can take some abuse, I dont want to say the heads are fragile but over the years they have been the source of problems on Supercharged engines and/or when over heated.
My own 99 3.4 Supercharged is on its second set of heads which were installed at 89k after developing cracks from pre detonation associated with the supercharger, Im at 134k now and everything looks good but the intake, fuel system, and cooling system are highly modified to prevent a recurrance of cracked heads.
This truck was a Toyota factory replacement for a similarly equipped 98 TRD supercjarged truck that blew the heads apart after 15k miles. If anyone made better replacement heads for this engine Id probably buy them. If I ever have engine/head problems again Ill probably install a Chevy SB crate 383 with a supercharger and 700R4, yes more money but I know just how dependable the combo is as I presently run a stroked 4.3 (327 CI after stroke) with a vortec supercharger and lightly modified 700r4 in my 91 Jeep Wrangler, better mileage and equal hp with less build cost.

 

[ToyotaTruckTrends]

@mark P. Welcome to this site..

 

[mark P.]

Tbplus10,

Can you give me rough dollar figure for what I should spend on new heads and gaskets? So a Chevy engine can be fitted into a tacoma? wow...you must seriously know your stuff to pull that off Thanks again for advise.

Mark P.

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Thanks. Very useful indeed.

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thanks...glad to be here!

 

[tbplus10]

Somewhere close to $600 for heads and gaskets, truthfully if you decide to stick with the 3.4 and need heads look at a running takeout engine, itll be close to the same price.

The 4.3 is almost the same dimensions as the 3.4, a much easier swap, but by using an electric fan, aftermarket thinner radiator, and setting the engine back 2" a 350 fits, the 700r4 trans is 1.5" shorter than the toyota trans and the extra 1/2" can be taken up by shortening the slip joint. Chevy engines and Toyota trucks have been a natural fit for years. You never Heard of a Chevota?