I have this old Toyota Tacoma 1998. It needs a valve job and oil pump valued at $2400. My question is simple does it make sense to put this kind of money into a pick up that is this old…?
Please tell us how it was concluded that you need a valve job and oil pump
Low engine compression?
I don’t know how likely it is, but simply adjusting the valve lash . . . I believe it is adjustable on Tacoma engines of this era . . . may bring compression back to an acceptable level
As for the oil pump, I’ll say this . . . many guys guys misdiagnose the oil pump as being the reason for low oil pressure. It’s usually not the pump that is the issue . . .
As for the financial aspect . . . it really depends on the condition of the truck. What kind of use does the truck see, and how often is it used?
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My '87 still works well; It has only 155K miles on it though. Haven’t needed a valve job yet.
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Thanks for the responses. They determined it had low compression in one cylinder, something around 60 or 80. They also did a test to measure the amount of unburned gas at idle and at 3500rpm. They said it was off the charts at idle which indicated a valve trouble but at higher rpm’s the unburned hydrocarbon values dropped way down but still above the “normal” range.
taking to a new mechanic soon maybe I’ll ask about the valve lash.
The truck is in fine condition. It has 200k on it so am nervous putting 2,000$ is a bad idea.
thanks again.
As the song goes, “Ya gotta know when to hold 'em, know when to fold 'em”.
You could do a valve job on the 200k mile engine, bring the compression back up, and then have lower end give up the ghost.
So with that many miles on the engine, you either rebuild/replace the engine, or forget about it.
Spending $2000 on a partial engine rebuild is a waste of money.
Tester
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I agree with Tester and especially so because of the oil pump recommendation. If an oil pump is really worn out then it stands to reason that everything following it has to be worn also.
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Your engine’s bearings are lubricated by the oil pump forcing oil through arteries inside the engine parts and squishing it through the spaces between the (sleeve) bearings and their corresponding surfaces (see photo of main bearings to illustrate) creating a pressurized fluid barrier between the wear parts. From there it drips back into the oil pan to be filtered, pumped back through the system, and reused. Wear cause the spaces to grow, eventually large enough that the oil flows too easily and the pump can no longer hold the pressure up. Sort of analogous to blowing up a balloon with a pinhole in it.
Low oil pressure does not mean you need a new oil pump. It means there’s excessive wear between the surfaces. Very rarely does an oil pump actually wear out. Your oil pump is a loosely toleranced pair of interlocked impellers that spend their lives awash is fresh oil. Oil pumps lead pampered lives.
The excessive hydrocarbon levels (unburned gas in the exhaust) are another indication of excess wear. The cylinders wear, the rings wear, and the rings also lose their spring tension, which is one of the reasons they seal the cylinder so well. Once the wear process becomes excessive, aerated gasses blow past the rings as the piston tries to compress them, resulting in compression levels dropping, allowing poor combustion. This produces an exhaust stream with a high level of unburned fuel.
No, the valve job is not worth doing. Nor is the oil pump worth changing.
A compression problem has apparently already been documented. I assume from the post that the oil pressure problem has also been verified. Both are signs of engine wear that cannot be addressed with these actions.
One thing you could do is drop the pan, drop a cap, and check the bearing clearance. That should confirm bearing wear as the cause of low oil pressure.
The engine needs to be either rebuilt or replaced. IF the frame and body are in great shape without rust, and you want to keep the truck, I’d recommend a remanufactured motor. If not, and you hope to keep the truck, you could try to seek out a boneyard motor.
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It is very likely the oil pump replacement was recommended because it is leaking oil, not because it is attached to a worn out engine.
If you buy another truck it is probably going to cost a good deal more than that. So the question is whether the $2400 will get it back on the road and in good running condition for 50K more miles at least. If the truck has had all the recommended routine maintenance on schedule it needed over its lifetime and has been driven gently, probably a good bet to have the work done. If routine maintenance has been skipped or delayed, or the vehicle has had a tough life (hauling heavy loads, or driven hard) , probably time to find a new owner for this one.
If it was anything but a Tacoma, the vehicle with the single best resale value in the US, I would say ditch it and don’t look back. Maybe an option would be to try to find a buyer to whom you honestly explain what is needed. It may get you more than you’d guess as a sale (if you can sell it the condition it is in). I spend a lot of time on Tacoma forums. People are in love with that generation. If the frame is not rusting it can easily last 300K if you keep it up. Tough call.
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VERY important to make sure the valves are adjusted correctly. Only then can compression and emissions tests be at all valid!
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I’m with @GorehamJ on this one. Our family has a 99 Tacoma stick shift 4 cylinder, 4 wheel drive with 200,000 on it. It drives well and feels solid and competent, original clutch. It also gets little love notes stuck under the wiper blades from time to time - “If you want to sell this truck, please call me.” Check the adjustments and settings and if it still has poor compression consider a rebuilt engine.
I too have asked the owner of a small Toyota pickup in good shape if he’d consider selling.
I’ve owned both a '79 Toyota pickup and an '89, both before they started calling them Tacomas. The '79’s frame rotted out after almost 11 years, the '89 I had until it got hit by another vehicle. It had 338,000 miles on it and was still running well. I got 295,000 miles out of the original clutch.
These vehicles are bulletproof if properly maintained. Were I to buy another pickup, it’s the only one I’d consider.
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Thanks for all the input. Think I am going to either sell the truck as is or save up some cash in the next few months and fix it up…I am leaning toward fixing it up but having them really check the oil pump to verify it needs to be replaced which seems unlikely from what I have read here and other places.
Thanks again.
If you want to take a few steps forward in do-it-yourself, adjusting valves requires little in the way of tools. A Haynes manual will show you how.
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