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View Full Version : Engine rattling...timing belt?


Valgard
01-27-2006, 01:44 AM
For the resident mechanics out there.

My girlfriend's 1996 Honda Civic EX just started making a rattling noise when it starts up. It'll keep rattling for a bit while idling and then go away. Popped the hood and watched while she started it up (to make sure that nothing was loose and flapping about causing the noise).

Sound seems to be coming from the front of the engine. It's a sort of rattle/clanking - not incredibly loud but you definitely notice it.

My Haynes guide for my F150 says that this could indicate a bad timing belt/chain (but that's for a Ford truck).

Any ideas what else could be causing this? If it's the timing belt I assume that it needs to get fixed right away (so that her engine doesn't croak while she's cruising along the highway)...one online estimate I saw for this was in the $400-$600 range, does that sound about right? I'm going to call a few places tomorrow and see what they'd charge for that.

Thanks!

orangetruck
01-27-2006, 01:56 AM
I'm not sure which engine this is, but timing belts don't rattle. This engine has a belt, only the newer K series Honda engines have timing chains. It may need a valve adjustment, most 4 cylinder Hondas need that every 30,000 miles.

Valgard
01-27-2006, 02:04 AM
I'm not sure which engine this is, but timing belts don't rattle. This engine has a belt, only the newer K series Honda engines have timing chains. It may need a valve adjustment, most 4 cylinder Hondas need that every 30,000 miles.

When I was looking up parts for a "1996 Honda Civic EX" at Kragen it resolved to an L4 1.6 liter engine, no other choices listed.

Is that a pretty simple task for a mechanic? I'm going to show her how to change her oil, spark plugs and other simple stuff this weekend but I've never fiddled with valves.

Valgard
01-27-2006, 02:10 AM
I'm not sure which engine this is, but timing belts don't rattle. This engine has a belt, only the newer K series Honda engines have timing chains. It may need a valve adjustment, most 4 cylinder Hondas need that every 30,000 miles.

When I was looking up parts for a "1996 Honda Civic EX" at Kragen it resolved to an L4 1.6 liter engine, no other choices listed.

Is that a pretty simple task for a mechanic? I'm going to show her how to change her oil, spark plugs and other simple stuff this weekend but I've never fiddled with valves.

orangetruck
01-27-2006, 02:17 AM
I'm not sure which engine this is, but timing belts don't rattle. This engine has a belt, only the newer K series Honda engines have timing chains. It may need a valve adjustment, most 4 cylinder Hondas need that every 30,000 miles.

orangetruck
01-27-2006, 02:19 AM
Oops, sorry about the double post. Valve adjustment isn't for amateurs, but it isn't labor intensive. It usually costs about $100, and has to be done cold. The valve cover is taken off and the mechanic makes sure the cam is on the base circle of the lifter of the valve under adjustment, and uses a wrench and a feeler gauge to set the lash. It takes me about a half hour on my six cylinder BMW and it is about the same procedure on a Honda.

orangetruck
01-27-2006, 02:21 AM
You can do the valve adjustment yourself but it is a good idea to have someone show you how or supervise you, since if you get them too tight you will burn the exhaust valves and need a head job, which costs about $2000.

Valgard
01-27-2006, 02:22 AM
Oops, sorry about the double post.

Likewise. The Gremlins are active tonight :-)

Valve adjustment isn't for amateurs, but it isn't labor intensive. It usually costs about $100, and has to be done cold. The valve cover is taken off and the mechanic makes sure the cam is on the base circle of the lifter of the valve under adjustment, and uses a wrench and a feeler gauge to set the lash. It takes me about a half hour on my six cylinder BMW and it is about the same procedure on a Honda.

OK, that's not bad.

Gary T
01-27-2006, 02:08 PM
The description of the symptom sounds very much like a loose exhaust heat shield. Usually you can verify that by pounding along the exhaust system with the heel of your fist. While it's not impossible to have noise related to a timing belt, it's not common, and I wouldn't expect it to go away after the car runs for a while. Exhaust noises, on the other hand, sometimes do go away as the pipes heat up and expand.

My Haynes guide for my F150 says that this could indicate a bad timing belt/chain (but that's for a Ford truck).
I doubt it says "belt/chain," because I've never heard of an F150 with a timing belt engine. Timing belts and timing chains perform the same basic function, but in this context they're apples and oranges, and it's best not to conflate them. Rattiling is not uncommon with worn timing chains.

I agree that it's wise not to attempt a valve adjustment without guidance from someone experienced and knowledgeable about it. It's not so much that it's hard to do, but that it's not hard to do it wrong, and as mentioned above, the consequences for that can be costly.

gotpasswords
01-27-2006, 03:32 PM
My first guess is dry lifters - oil drains out of them and they're noisy until re-pressurized with oil. Is the noise clattering at first, then smooths out? That's usually a pretty harmless, if noisy, condition.

At best, a timing belt might make a flapping sort of noise. Perhaps the belt tensioner or water pump is sticking?

This engine is an "interference" engine, which means you'll pretty much need a new engine at the very instant the belt breaks as the pistons will smash into the valves. The usual recommendation is to replace it every 60,000 miles. The belt also drives the water pump - a siezed pump bearing could also cause catastrophic engine failure.

Valgard
01-27-2006, 03:47 PM
The description of the symptom sounds very much like a loose exhaust heat shield. Usually you can verify that by pounding along the exhaust system with the heel of your fist. While it's not impossible to have noise related to a timing belt, it's not common, and I wouldn't expect it to go away after the car runs for a while. Exhaust noises, on the other hand, sometimes do go away as the pipes heat up and expand.

My Haynes guide for my F150 says that this could indicate a bad timing belt/chain (but that's for a Ford truck).
I doubt it says "belt/chain," because I've never heard of an F150 with a timing belt engine. Timing belts and timing chains perform the same basic function, but in this context they're apples and oranges, and it's best not to conflate them. Rattiling is not uncommon with worn timing chains.

I agree that it's wise not to attempt a valve adjustment without guidance from someone experienced and knowledgeable about it. It's not so much that it's hard to do, but that it's not hard to do it wrong, and as mentioned above, the consequences for that can be costly.

Sorry, I was using the terms interchangeably. My F150 uses a serpentine belt and an actual timing chain. The Haynes reference is to the chain, IIRC. The thingy, in technical terms :-)

I'll check the exhaust heat shield and if valve work is needed I'm happy to leave that up to a mechanic.

Gotpasswords, are the lifters oiled by the normal engine oil? That is, if her oil level is low will a normal oil change (including a fillup with the proper amount of oil) take care of that problem?

GargoyleWB
01-27-2006, 03:52 PM
Interesting, I'm curious also.

I have exactly the same thing, a 1996 Civic EX. The rattle was the first thing I thought of when I clicked on the thread and, lo and behold, the same car!

The rattle comes and goes, but usually smooths out after 10 or 15 minutes, and usually happens in cold/damp weather. It sounds exaclty as if I had a loose fan, but listening to the rattle with the hood open, I've never been able to track the source.

I eventually just figured it to be "one of those Honda things" and shrugged it off.

For what it's worth, I bought the car with 20k miles on it, and it rattled then. I'm up to 150k, it still rattles in the same way, but seems none the worse for wear. I like to think of it as getting a free "baseball cards in the spokes" upgrade :)

Valgard
01-27-2006, 03:56 PM
Interesting, I'm curious also.

I have exactly the same thing, a 1996 Civic EX. The rattle was the first thing I thought of when I clicked on the thread and, lo and behold, the same car!

The rattle comes and goes, but usually smooths out after 10 or 15 minutes, and usually happens in cold/damp weather. It sounds exaclty as if I had a loose fan, but listening to the rattle with the hood open, I've never been able to track the source.

I'll post the solution when we've got it fixed. Just spoke to my g/f, she had the timing belt replaced at 90k miles (it's got about 100k-105k on it now) so I doubt that's the problem.

GargoyleWB
01-27-2006, 04:01 PM
Oh, and I was quoted about the same as the OP for a timing belt replacement ($400-600). There is significant labor involved, because you have to drain the coolant and partially dismantle the water pump to get to the timing belt. My mechanic called it such a pain in the butt, that if he let me also just replace the water pump at the same time, he'd do the new water pump for no charge since it was overdue for replacing anyway and he didn't want to repeat the ordeal :)

gotpasswords
01-27-2006, 05:16 PM
Gotpasswords, are the lifters oiled by the normal engine oil? That is, if her oil level is low will a normal oil change (including a fillup with the proper amount of oil) take care of that problem?
Yes, the full term is "hydraulic lifters" and they're self-adjusting shock absorber-like things that need to be filled with engine oil to work properly.

I just had a "duh" moment - if your engine needs periodic valve adjustments, you don't have hydraulic lifters. You'd have solid lifters, which are solid bits of metal that transfer the push from the camshaft to the valves.

More on the water pump - not replacing it when you replace the timing belt is one of the dumbest ways you could ever try and save money on car maintenance. When you get the belt out, you're staring right at the pump, and the cooling system's already been drained. It's like climbing to the top of Mt Everest and not taking a picture. You've already done 98% of the labor, why not spend the $50 for a new pump and not worry about it breaking 1,000 miles later, requiring you to pay another $500 in labor?

danceswithcats
01-27-2006, 06:08 PM
One way to locate an underhood noise is by using a length of heater hose-put one end in your ear and point the other end at or touch specific components-effectively a poor man's stethoscope. Just keep it out of the fan, or you'll have two shorter pieces of hose. ;)

Rick
01-27-2006, 06:23 PM
The description of the symptom sounds very much like a loose exhaust heat shield. Usually you can verify that by pounding along the exhaust system with the heel of your fist.
It is strongly suggested that you do this with the engine cold. :D
Another cause or rattling noises from the front of an engine can be bearings in idlers for belts starting to self destruct. If one of these ball bearings self destructs the result can be spectacular, and expensive.

Valgard
01-27-2006, 06:32 PM
It is strongly suggested that you do this with the engine cold. :D
Another cause or rattling noises from the front of an engine can be bearings in idlers for belts starting to self destruct. If one of these ball bearings self destructs the result can be spectacular, and expensive.

At this point I'm hoping to find a part with a small label that identifies it as "Honda X-17-MW7 Useless Rattling Widget" that can simply be disconnected.

danceswithcats
01-27-2006, 07:50 PM
At this point I'm hoping to find a part with a small label that identifies it as "Honda X-17-MW7 Useless Rattling Widget" that can simply be disconnected.Some models were equipped with more than one. ;)