Acura Integra: Blown Timing Belt Destroying the Valves?

Timing belt blew in the mountains of West Virginia. Some nice locals got me to a shop that replaced it, but no compression in the #2 cylinder and it doesn’t run smoothly anymore (loss of power, missing on idle). One national chain shop back home said I need a head job to replace bent valves. An independent shop down the road told me my engine, 4-cylinder, dual-overhead cam, interference engine would NOT run at all if I had bent valves, so most likely I just need a valve adjustment and some tune up to the ignition system.

Anyone familiar with this kind of engine? I drove it back from WV to Charlotte, NC, so is this guy right that I didn’t bust up my valves since the car runs? He thinks the national chain guys are trying to rip me off.

An interference type engine can run with bent valves. The question is how many are bent.
The intake valves are the ones that bend as the heads on the intakes are larger. The number that are bent falls mostly into the luck category. The engine may bend one and stop rotating immediately or it may roll on through and bend every one of them.

So yes, an engine with damaged valves on 1 or 2 cylinders can run but will run poorly.

The issue I would have is that the shop replacing the belt actually went about this a bit backwards. You do not have to replace a belt to determine if there is a serious problem with valves, low compression, etc.
There are several easy methods to determine if bent valves exist and apparently they did not use any of those while simply replacing the belt.

The national chain is quite likely correct and your indendent shop would be correct IF every intake valve in the cylinder head was bent. Hope that helps.

Year and mileage on this Integra ?

It’s a 1999 and has 165,000. I’ve heard the engine should last 250-300K, but the timing belt that blew was original and I should have had it changed at 60K. Taking it in to the independent guy Monday to see if his valve adjustment idea fixes it, and if it doesn’t maybe he’ll give me a credit towards the head job.

One issue that’s bothering me is the noise I heard when the timing belt blew on the highway. It sounded like dropping a bunch of change on the sidewalk, like a metallic clinging sound. Nothing loud, but I figured the noise was the valve stems smashing into things. Any other ideas of what that could have been?

Thanks for the input. But running on 3 cyls instead of 4 would eventually burn up the engine, correct?

If the car ran poorly before the timing belt broke, the problem is the potential need for a valve adjustment and tuneup. If the engine ran fine before the belt broke, the problem is probably valve damage. Yes, an interference engine can run with bent valves, it just depends on how many get bent and how badly they bend. It is also possible for an interference engine to break it’s timing belt and cause no valve damage, although it is exceedingly rare. I have seen it once, on a Nissan Quest minivan. Oddly, the owner was still really upset about the repair bill. I am certain you have at least one bent valve, probably more. You do need to get this fixed ASAP, before you cause more damage to the car by driving it the way it is.

Possibly. This can clog and/or overheat the converter and in turn may cook piston rings and valve seals if severe enough.
This will be followed by oil consumption which then makes the converter problem even worse.
It’s a vicious cycle.

Honestly, this car should be parked until repaired and I think inspection of the valve adjustment is an exercise in futility.

If your guy wants to assume a tight valve is causing this then what does he think is the result of a tight valve? A burned valve is the result and bent or burned, the head must come off and the valve(s) replaced.

If he’s going to go this route then pull the valve cover, rotate that cylinder’s piston to TDC, and see how much slop there is in the intake valve train. If it’s very loose the intake valve has about a 99%+ chance of being bent. This is due to the valve stem bend which is not allowing the valve to seat completely and of course this means the valve clearance will be excessive.

Nope, that’s what it was. That’s the sound of dying valves.

Before you get it fixed, look into prices for an engine swap. Your Teg uses either a B18-B or a B18-C engine. (GS, LS, and SE are B, GS-R is C). Assuming you don’t have a GS-R, you can get a replacement engine pretty cheaply. Price both options out.