I NEED HELP!
Thread Starter
Instructor
Joined: Aug 2001
Posts: 156
Likes: 0
From: Toronto Ontario
I NEED HELP!
I've noticed a rattling sound from under the hood the last couple of weeks. I went to my mechanic and he says that it's a loose rod in the engine. That's not what I wanted to hear.
So now I've got a dilemma. I would assume that a rebuild would probably be the best long-term course of action. But do I have any other options...that is, economically feasible options? My mechanic quoted me about $2500 CAD for a rebuild...and that's really not what I had in mind right now.
I also asked him if it's okay to drive...he said it should be fine, but I don't want to risk being stuck somewhere with engine trouble. Any advice?:confused:
Thanks all...and anyone from the Toronto area who can help me out would be much appreciated.
So now I've got a dilemma. I would assume that a rebuild would probably be the best long-term course of action. But do I have any other options...that is, economically feasible options? My mechanic quoted me about $2500 CAD for a rebuild...and that's really not what I had in mind right now.
I also asked him if it's okay to drive...he said it should be fine, but I don't want to risk being stuck somewhere with engine trouble. Any advice?:confused:
Thanks all...and anyone from the Toronto area who can help me out would be much appreciated.
Le Mans Master
Joined: Jan 2001
Posts: 9,244
Likes: 221
From: Dryden MI
Re: I NEED HELP! (78RedShark)
I had what sounded like a rod knock. I checked the bolts that fasten the torque converter to the flywheel and found a loose bolt causing the noise. I tightened bolts and supposed rod knock went away. Maybe you can be so lucky, it is worth a look. Roger L. Gibbons
Le Mans Master
Joined: Aug 2000
Posts: 6,362
Likes: 7
From: Brazos TX
Cruise-In IV Veteran
Cruise-In V Veteran
Re: I NEED HELP! (78RedShark)
Another possibility is a stretched timing chain. It can slap the timing cover and sound like a rod. The only way to know is to pull the oil pan and have a look at the rod bearings. Once the pan is off it's easy to look at the timing chain.
Burning Brakes
Joined: Dec 2000
Posts: 1,183
Likes: 2
From: Des Moines Iowa
Re: I NEED HELP! (78RedShark)
Bad rod bearings usually produce a noise that's usually described as a "knocking" sound in an engine, not really what most people would describe as a "rattle".
If indeed, you've got a bad rod bearing, would strongly suggest NOT driviing the vehicle too much, or too fast.
Is the noise the same regardless of whether the engine is cold or fully up to operating temperature? Does the noise increase in frequency with an increase in engine speed (rpms)?
How is your oil pressure when engine is fully warmed up? Should be 20 to 30 lbs. of pressure at 1,000 rpms, although it's said you can 'get by' with as little as 10 lbs. per 1,000 rpms.
Should be able to isolate somewhat, location of the noise/rattle/knock, with use of a 'mechanics stethascope', which can be purchased at many auto parts stores for around $10.
If indeed, you've got a bad rod bearing, would strongly suggest NOT driviing the vehicle too much, or too fast.
Is the noise the same regardless of whether the engine is cold or fully up to operating temperature? Does the noise increase in frequency with an increase in engine speed (rpms)?
How is your oil pressure when engine is fully warmed up? Should be 20 to 30 lbs. of pressure at 1,000 rpms, although it's said you can 'get by' with as little as 10 lbs. per 1,000 rpms.
Should be able to isolate somewhat, location of the noise/rattle/knock, with use of a 'mechanics stethascope', which can be purchased at many auto parts stores for around $10.
Melting Slicks
Joined: Mar 2002
Posts: 2,313
Likes: 0
From: The cure for the blues is eight cylinders roaring
Re: I NEED HELP! (john's '81 mouse)
Dont drive it you can warp the rod or damage the crank to make it unusable for a core exchange .A bad rod will sound something like spinning a ball bearing around in a tincan ecept deeper with a knock thrown in and will sound like its coming from the oil pan.If you can here it its bad .If its just the bearing you may get away with just putting in a fresh crank and bearings.
[Modified by Wightnite, 5:45 PM 4/18/2002]
[Modified by Wightnite, 5:45 PM 4/18/2002]
Thread Starter
Instructor
Joined: Aug 2001
Posts: 156
Likes: 0
From: Toronto Ontario
Re: I NEED HELP! (john's '81 mouse)
Yes john, the knocking sound is faster as the rpm's increase. I've also noticed at times that the noise goes away...it's not quite consistent, but it happens more than 75% of the time...
Drifting
Joined: Oct 2000
Posts: 1,825
Likes: 56
From: Shawano WI
Re: I NEED HELP! (78RedShark)
I would look at the flexplate. Stock automatic flexplates are prone to cracking and when they do it sound just like a rod knock. Pull the inspection cover and look if you can see any cracks from the crank bolt holes going towards the outside of the plate. Years ago I worked for a Chevy dealer and we used to replace 3 or 4 flexplates a week.
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