I have a 91 hatchback, 1.5L, 140,000 miles. I just started hearing a knocking type sound coming from my engine. It seems to dissapate upon exceleration, it is worse at idle. It seems to be from the driver's side of the car. Has anyone heard that type of noise from a bad waterpump or timing belt tensioner? Tonight I'm going to remove the top belt cover and see if it is obvious that it is either one.
I hate to replace those if it is a rod in the engine as I do have a spare engine to put in.

I believe I'm going to have to remove the dreaded crankshaft pulley bolt to replace either one?

 

Tensioner usually makes more of a grinding sound... bad bearing. Water pump makes a similar sound (grinding) sometimes but the most common problem is the seal leaks. That's why you replace it when doing a t-belt. You'd most likely head a rod knock WORSEN on acceleration/load if that was the case. You sure it's not valves (possible worn adjusters or valve stems)? You can hold a long screwdriver to your ear and place it against various spots on the engine to try and isolate the sound. Is the sound better, worse or the same on a hot engine vs a cold engine?

My '91 is tight as a drum but it still makes some interesting (faint) noises at idle...... for what that's worth.

 

The knocking/rapping sound is the same hot or cold. It was 40 degrees this morning when I started my car and it sounded the same after I drove ten miles. It does seem to go away upon acceleration, not as loud. It doesn't sound like valves out of adjustment, but I might check them as well as checking the belt to see if it's loose. I had thought another possibility would be alternator bearings, but its pretty loud for that.

 

Sounds like you-re on the right track... try that screwdriver technique and see if you can pinpoint the source of the sound.

Watch clothing, appendages and loose "bling" when fumbling around a running engine :doh:

Another thoughts... would it be an exhaust part... like a heat shield? They usually make a "tinny" rattling sound at idle.

 

It could definately be a water pump... My g/fs Civic LX engine had a similar 'knocking' sound... I was hoping it wasnt a rod knocking... Turns out it was the water pump, it completely came off the 'axis' or bearing or whatever it is it sits on... The bad part was, she drive it home overheated when it finally blew... :doh: Didnt hurt the engine tho atleast not right then and there... I put a new belt and stuff on, and it ran fine... Unfortunately, the engine did die about 6 months later... Whether or not it was related, I dont know for sure...

 

It WAS related

 

Well it is my waterpump. Of course I can loosen the crankshaft bolt. The waterpump is so bad I don't dare drive it to a garage to get them to loosen the crankshaft bolt. I've heard that it could cause the belt to break or come off then the valves hit the pistons. I put the car in gear and put the spark plugs back in and the crank just turns. I've heard the screwdriver in the flywheel doesn't work. I've also heard on here that some people put the wheel on the ground and have someone put the brakes on while loosening the bolt, but how would that make any difference?
Anyway, I'm thinking of breaking off the lower timing belt cover to get to the waterpump. Any thoughts on that? All I really need to do is to remove the timing belt covers to gain access to the waterpump for replacement. Of course later, I would go to a garage and have them loosen the crank bolt and replace the lower timing belt cover with a spare I have now.

 

I replaced my timing belt and water pump this weekend while doing my clutch. I pulled all the plastic cowlings off then put the tires back down on the ground. Placed the car in gear and then had my son stand on the brakes while I used a 6' cheater bar to break the crankshaft bolt loose. His standing on the brakes locked up the entire drive line including the craknshaft but of course it did not hurt that I had just put a brand new clutch in there so it helped keep it from slipping while I broke the bolt free.

 

I just tried the two bolts in the crank method and managed to bend my radius arm in a little. What will that effect? I'll try the brakes on method, but I need to get another extension to reach out past the wheel.

 

I got the water pump off by cutting off part of the lower cover. It was definately the waterpump. I hear loose metal inside and it turns hard.

Anyone know if a radius rod from a 91 LX, 1.5 will fit on my 91 hatchback, 1.5?

My radius rod is bent a little, not sure how this will effect steering.