1994 Integra: Bad Valve Adjustment?

I have a 1994 Acura Integra LS automatic with 165k miles. I had a valve
adjustment done on the car. Immediately after the work was done and
since that time the car has had poor gas mileage, a very rough idle,
and loss of power. I had abolutely none of those problems before the
adjustment. Before I take it back into the shop I would like to know if
a bad valve adjustment could be the source of these problems and how it
should be remedied. Also, are there any long-term risks associated with
a bad valve adjustment?

 

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Who did the adjustment? It sounds like they also jumped your timing belt
a tooth or two.

Same engine as the first generation CR-V. You want to be sure that (when
they redo it) they set the valves to the 'loose' side of the specs. . .
..

http://www.hondasuv.com/stg/viewtopic.php?t=16836&highlight=burnt+valves
http://www.hondasuv.com/stg/viewtopic.php?t=14753&highlight=burnt+valves

I hope you didn't drive it fast or far like it is. You'll smoke a
valve. :-(

'Curly'

 

Normally a valve adjustment itself doesn't bring about those problems - it
sounds like the timing belt has slipped. First and most critical question -
is this the original timing belt? If the answer is "yes" you are driving on
borrowed time.

If the belt was changed a few years ago when it was due, the danger of a
flubbed valve adjustment is that the valves may have been set too "tight."
That often leads to burned valves. "Loose" valves make a lot of clatter but
are not a risk of damage.

If the timing belt jumped because the engine was turned backward (clockwise)
during the valve adjustment the shop owes it to you to make it right, even
if (*especially* if) valve damage has resulted. If the belt is overdue for
replacement - that is, if it is the original - you may have some bargaining
to do. They can't be wholly responsible for failure of a 12 year old belt.

Mike

 

It was a local Honda dealership. So, if I suggest to them that they
"jumped my timing belt a tooth or two" they'll know what I'm talking
about? If I did burn a valve because of their bad adjustment wouldn't
it be their responsibility?

 

Mike,

The timing belt was replaced at around 95k. So, it is not the original
belt.

 

That's good. The thing to do is take it back and let them know it is running
much worse and you are confident they will make it all better. I'm sure they
will live up to your hopes!

Mike

 

concur with mike & curly - belt skipped while it was being turned the
wrong way. have them re-time the cam belt and adjust the belt tensioner
correctly, then you should be set. clearly it wasn't done properly when
the belt was last changed - another symptom of incompetency that would
make me very wary.

which brings me to the next point: for the future, i'd consider finding
another shop. you got the junior junior wrench's assistant here, twice
in a row. personally, i'd rather have this critical and potentially
/very/ expensive stuff done by someone with both experience and a
reputation to worry about. independents can be great in routine stuff
like this because they've done their time at the dealership, know their
trade, and are in business to stay in business, not depend on a captive
audience like the dealer.

 

I also suspect your timing belt is very loose and now might be a good lime
to replace it and the tensioner. My tensioner was bone dry in my 95 Civic
VTEC with 190,000 miles. The timing belt was orginally done by the dealer
at 110,000 and had over 1.5 inches of deflection at 190,000 vs. a little
over .25 inches after the second belt change. And most of us would agree
that these belts don't stretch! Good luck.

 

Update: I brought the car in and pointed out the issues you guys
brought up. It did turn out to be that the timing belt had, in fact,
jumped one tooth. However, they insisted that it was purely a
coincidence and the valve adjustment had nothing to do with it. I asked
why would it jump immediately the day after the valve service. He
replied although there is only 65k on the timing belt, that because it
has been over 6 years since it was replaced that the timing belt
probably is due and a little worn and that could've cause it to jump. I
told him I didn't agree with that scenario, but he wouldn't concede.

Seeing that was going nowhere, I then asked assuming that is was a
coincedence why didn't they notice that before the last two times I was
in with this problem? He replied that they did check the timing and it
was just a little off -- but still within the normal range. I then
asked to talk to the service manager who just happened to be out of the
office.

When I talk to the service manager what "proof" can I show him that the
valve adjustment could have caused the timing belt to jump a tooth? I'm
not a mechanic by any means, so I just can't say "because I saw it in
an online newsgroup." Is there something official from Honda or Acura
that I can find online?

Anyway, the car runs great now. No more rough idle at all. I haven't
gone through a tank of gas yet, but I'm pretty positive that will be
better, too.

 

Maybe the answer is that it's good you learned about their integrity at a
modest cost, rather with something more expensive.

"If you loan a friend $20 and they never pay you back, it was worth it." -
unknown

Mike

 

Not sure how adjusting the valves would cause the belt to slip.
Possibly, if the belt were loose and the engine was rotated backwards
aggressively, then maybe. If the valve timing is now advanced (i.e.
valves opening too soon), that could indicate that the slippage
occurred in that manner.

If they are complete idiots, anything is possible.

 

Rotating the engine backward, even gently, is definitely capable of causing
the belt to jump. Fortunately the cover was still off when I did that <8^P

Mike

 

it's not the actual valve settings that cause the belt to jump, it's the
fact that if the belt is already loose, when the technician
*incorrectly* turns the crank the wrong way, a loose belt will jump.
and here's the clincher, not only is a loose belt easily apparent when
you get the cover off, you can /see/ it jump as the crank rotates!!!

bottom line:

1. if the belt was loose, it wasn't done right in the first place -
belts don't stretch.

2. the tech turned the crank the wrong way, hence the jump.

3. checking for loose belt is part of the job when doing the valve
lash!!! if that wasn't done, and they sent it out the door with a belt
that was not only loose but jumped, it's /definitely/ their problem.
just like it's their problem if they work on the wheels, don't tighten
the bolts on replacement, and one falls off on the freeway home.

the belt tensioning procedure is all in the honda service manual,
including instructions to only turn the crank in one direction. i'd
call honda usa's customer service line and talk it through with them.
this vehicle wasn't serviced right, and you shouldn't have to pay for
the remedy to their error.

 

Well, there you go. I assume you saw it jump on the cam sprocket.

And I am pretty sure that if the belt slipped while the engine was
turning forward, the valves would always be retarded. If the valves
are advanced, it could only happen when the engine was turning
backwards and it indicates that the mechanic made a mistake when
adjusting the valves. I'm guessing that he isn't very familiar with
Hondas.

 

Right. Fortunately it was in front of my face as I was moving the crankshaft
and I was watching it to align the timing marks. The belt lifted up almost
immediately as the cam gear began to move. IIRC I had planned to turn the
crank quite a distance, so I didn't stop in time to prevent the belt from
jumping the whole tooth.

 

AND...as the tech that did the job, you FELT it jump (oops!), but DIDN'T
TELL ANYBODY.