ticking under hood

[BodybyFisher]

You might have the flywheel bolts retorqued and check for a cracked flywheel.

[nwtnan]

You might have the flywheel bolts retorqued and check for a cracked flywheel.

Any idea of where I can get the torque specs from......please remember you are talking to a woman......simple terms when it comes to cars. lol

[Bruce Nunnally]

Nice listening device.

So you have a ticking sound "after it is warmed up and idling" which is coming from the rear of the engine or the front of the transmission?

It does not make a ticking noise while cold?

Does the noise continue when the car is underway?

Does the engine have much movement when you rev it in park, which might suggest that the engine mounts are worn?

[nwtnan]

I thought you would like my hose stethoscope.....it was a black 4 foot long peice of hose worked great!

My son-in-law is now telling me to him it sounds more like a knocking noise.

It is very slight when cold.....gets louder when it warms up and continues while we are driving.

I am not sure about the movement as the engine is so smooth running.

I will go out and check it and get back to you.

Thanks

[Bruce Nunnally]

General engine sound diagnosis: http://www.gmgoodwrench.com/_res/pdf/Engin...ust%202004).pdf

Noise Symptom Description Check or Test (pick one, then read diagnosis):

Double knock Light crankshaft-speed knocking noise heard for the first few minutes after start-up.

Check for a loose piston pin.

Rattling − Light, irregular, "dieseling" or "marbley" rattle, ticking noise heard for first few minutes of

start-up.

− Light, regular, camshaft-speed ticking noise, heard best when

the engine is increased to 2000 rpm, then released to idle

− Check for several loose piston pins.

− Check for defective/misaligned balance shaft bearing.

Thumping Light, regular thumping noise heard best near accessory drive belt pulleys.

Check drive belt pulley tensioner. Adjust to specified deflection. Check pulley alignment.

Dull Knock Heavy, regular, dull metallic knock that occurs on acceleration, under load.

Check for incorrect main bearing clearances.

Chirping, Squealing Steady "chirping" at nominal speeds, loud squealing upon acceleration or

tight turns. Check drive belts for looseness/glazing; check pulleys/tensioner; check for paint in grooves.

General Knock Includes dull, regular and metallic knocking.

Check for incorrect connecting rod bearing clearances, piston scuffing, tight piston pin, clogged anti-drainback filter.

Sharp Knock Light, regular, sharp metallic rapping of clattering knock heard best at speeds between 25 and 35 mph. Check for loose flexplate bolts, cracked flexpate, incorrect connecting rod bearing clearances. Repair as required.

Loud pop GM Northstar - Pop when key is released after extended crank and failure to start.

May be a normal pressure release from the fuel induction system/intake manifold. Refer to GM Bulletin 57-60-02.

Valve train noise − Worn or defective camshaft may be problem.

− Loose rocker arm attachments

− Worn rocker arm or pushrod

− Broken valve springs

− Sticking Valves

− Worn, dirty, defective lifters

− Defective fuel pump, pushrods

− Low oil pressure

− Worn valve guides

− Collapsed Lifters

− Check for popping noise through throttle body;

perform visual inspection; check with dial indicator.

− Visual inspection; service as required.

− Diagnosis cause and repair.

− Visual inspection; vacuum gauge test.

− Visual inspection; vacuum gauge test.

− Visual inspection.

− Visual inspection.

− Check oil pressure; repair as needed.

− Perform vacuum test; use dial indicator to check

wear.

− Oil drained out of lifters, replace as indicated.

Tick − GM C/K vehicles - On cold start at low temperatures during engine deceleration after idle

flare. Not consistently repeatable.

− Confirm proper VCM calibration. Refer to GM Bulletin 99-06-04-014 for details.

Knock, engine cold. Continues for 2 to 3 minutes. Increases with torque.

− Flywheel may be contacting splash shield.

− Loose or broken torsional damper or drive pulleys.

− Excessive piston-to-bore clearance (piston slap).

− Bent connecting rod.

− Perform visual inspection.

− Remove accessory belts; perform visual inspection.

− Check with bore gauge and T-gauge micrometer.

− Perform visual inspection.

Heavy knock, engine hot, torque applied.

− Broken harmonic balancer or pulley hub.

− Loose torque converter bolts.

− Exhaust system grounding out.

− Cracked flywheel, loose rivets.

− Incorrect main bearing or rod bearing clearance.

− Remove drive belts; perform visual inspection, service or replace as required.

− Visual inspection.

− Visual inspection; carbon knock possible.

− Visual inspection.

− Visual inspection.

Light knock, engine hot, under light load conditions.

− Pre-ignition; ignition control problems; detonation.

− Poor fuel quality

− Loose torque converter bolts.

− Exhaust leak at manifold.

− Excessive rod bearing clearance.

− Check engine codes and ignition timing settings; reset to specifications; check EGR for blockage.

− Owner input; use known good fuel.

− Visual inspection.

− Visual inspection.

− Visual inspection

Start-up knock, lasts a few seconds.

− Timing chain tensioner not properly set.

− Improper oil viscosity.

− Bearing knock.

− Hydraulic lifter bleed down.

− Check filter with anti-drainback valve.

− Change oil; check engine performance for knock.

− Confirm that filter has anti-drainback valve.

− Check requires special equipment.

Knock at idle, engine hot.

− Drive belts too tight; accessory belt pulley bearing loaded.

− Improper oil viscosity.

− Noisy piston pin (double knock).

− Loose torsional damper.

− Remove accessory belts; observe change, if any.

− Change oil; check engine performance for knock.

− Short out suspect cylinder; noise should disappear.

− Perform visual inspection with engine under load.

[nwtnan]

Wow this site and you people are amazing!!!

I have learned more about cars in the last few days then I have in my whole life....my family keeps laughing at me as they cannot believe I picked up all this auto knowledge.

Sure am glad I supported this site....best $20.00 I have ever spent.

Getting back on topic I checked the engine, reved it up and it barely moved....had my son in law (who knows about cars) check the mounts and they all looked tight.

[Bruce Nunnally]

So does the symptom sound most like this description?

Light knock, engine hot, under light load conditions.

− Pre-ignition; ignition control problems; detonation.

− Poor fuel quality

− Loose torque converter bolts.

− Exhaust leak at manifold.

− Excessive rod bearing clearance.

− Check engine codes and ignition timing settings; reset to specifications; check EGR for blockage.

− Owner input; use known good fuel.

How long did the car sit before you bought it? Could it have bad gas in it?

On a separate topic, autolit.com has or had a full brochure on your type of hearse! See their (expired) auction here: http://cgi.ebay.com/1981-Cadillac-Buick-Su...1QQcmdZViewItem but you might try emailing them to see if still available.

[nwtnan]

So does the symptom sound most like this description?

Light knock, engine hot, under light load conditions.

− Pre-ignition; ignition control problems; detonation.

− Poor fuel quality

− Loose torque converter bolts.

− Exhaust leak at manifold.

− Excessive rod bearing clearance.

− Check engine codes and ignition timing settings; reset to specifications; check EGR for blockage.

− Owner input; use known good fuel.

How long did the car sit before you bought it? Could it have bad gas in it?

On a separate topic, autolit.com has or had a full brochure on your type of hearse! See their (expired) auction here: http://cgi.ebay.com/1981-Cadillac-Buick-Su...1QQcmdZViewItem but you might try emailing them to see if still available.

That sounds about right.....timing is getting checked today. I see the exhaust leak at the manifold is mentioned again......the whole car had an inspection done just before I bought it. The exhaust was all checked and passed.....so I don't know. Torque converter bolts were checked last night good and tight.

The car sat for a couple months before I bought it and apparently was a working vehicle right up until then....with the condition it was in I doubt that.

The car has had problably 8 tanks of gas go through it since I aquired it as it had to make the long trek from Edmonton to Yellowknife.

I checked out the brochure....thanks for the info.

[nwtnan]

Okay so here is what we have done...oil changed to 10/30 new filter, Transmssion fluid changed and filter, new distributor cap and rotor, Fly wheels bolts were nice and tight, no cracks on flywheel, timing done, idle screws were set to spec (I think they are too low now tho), engine runs nice and smooth and quiet....sounds like a top EXCEPT the knocking from torque converter area is still there. When we held the stethoscope up to it it was very definately there and no where else.

Could this still be an exhaust leak??

I am getting frustrated!!

[BodybyFisher]

Check these links, torque converters, flex plates and flywheels can be a source of noise:

http://dodgeram.info/tsb/1989/09-11-89.htm

http://www.jasperengines.com/pdf/AllisonTransLeakTB.pdf

http://www.valvoline.com/carcare/articlevi...1tc&print=1

http://www.z28.com/forum/showthread.php?t=1230

http://forums.stangnet.com/showthread.php?t=472460

http://www.babcox.com/editorial/bf/bf90054.htm

[nwtnan]

I have taken this car to 2 mechanics one at Ford and 1 at the GM dealer both have a difference of opinion to the problem. Finally took it to a heavy duty mechanic (also a friend of mine) and he is telling me it is the piston rod which means I will be having a rebuilt engine sent up.

Question to you all .......the 8 6 4 engine in my hearse was only in production for 1 year....very very hard to get....imposible here in the Canadian Arctic, what I need to know is (this might be a real tough one) but what other engines would fit in this chassis if any??

Much thanks once again for any help you can give me

[KevinW]

Question to you all .......the 8 6 4 engine in my hearse was only in production for 1 year....very very hard to get....imposible here in the Canadian Arctic, what I need to know is (this might be a real tough one) but what other engines would fit in this chassis if any??

If your hearse was built on the Commercial Chassis, it would be equipped with an M4ME QuadraJet (not the DEFI V8-6-4). A sedan-based hearse might have the DEFI engine; if you wish to retain this, it would be necessary to match the displacement (or hack the ECM!), in which case you'd be limited to most 1980-81 Cadillacs, and 1982-84 Commercial Chassis or Fleetwood Limousines.

In the event the existing engine is carbureted, or you wish to convert to carburetion (quite simple), any 1977-79 Cadillac 425 from a RWD application would work. FWD versions have a different oil pan and manifolds, as would be the case for a 1968-1974 Cadillac 472 or a 1970-1976 Cadillac 500. Basically, you could get it working, without the hassle of adapting engine accessories, by using a 472/500/425/368 Cadillac V8 from 1968-1981 (plus a limited number of 1982-84 models with the 368).

One could deviate from originality even further (dictated by convenience!) by using any drivetrain from a 1977-1996 RWD B/C/D car, adapt or transplant some of the accessories, change the transmission cross-member, and adapt the driveshaft as required, and so forth. The later fuel-injected engines entail the added complication of swapping manifolds or adapting EFI wiring harnesses, and ensuring the fuel system is compatible (SPFI require a higher operating fuel pressure).

Bottom-end failure on these engines is extremely rare. Given the typical use of such vehicles, carbon build-up is always an issue; a piece of carbon in the squish area could cause a knocking sound under all conditions, which can be fixed by some combustion chamber cleaner and spirited driving. Does the knocking change with load? Exhaust leaks typically get quieter once the manifold warms up. 368s tend to have a problem with loose exhaust manifold bolts.

[KHE]

I have taken this car to 2 mechanics one at Ford and 1 at the GM dealer both have a difference of opinion to the problem. Finally took it to a heavy duty mechanic (also a friend of mine) and he is telling me it is the piston rod which means I will be having a rebuilt engine sent up.

Question to you all .......the 8 6 4 engine in my hearse was only in production for 1 year....very very hard to get....imposible here in the Canadian Arctic, what I need to know is (this might be a real tough one) but what other engines would fit in this chassis if any??

Much thanks once again for any help you can give me

Before I went to all that trouble, I would plastigage the rod bearings - that will tell you what the clearances are. If the bearing clearance exceeds the factory spec, then you could repair the existing engine. If te crankshaft is not damaged, you would only need to install new rod bearings. Even if the crank was scored, it could be ground and service bearings used.

[nwtnan]

Question to you all .......the 8 6 4 engine in my hearse was only in production for 1 year....very very hard to get....imposible here in the Canadian Arctic, what I need to know is (this might be a real tough one) but what other engines would fit in this chassis if any??

If your hearse was built on the Commercial Chassis, it would be equipped with an M4ME QuadraJet (not the DEFI V8-6-4). A sedan-based hearse might have the DEFI engine; if you wish to retain this, it would be necessary to match the displacement (or hack the ECM!), in which case you'd be limited to most 1980-81 Cadillacs, and 1982-84 Commercial Chassis or Fleetwood Limousines.

In the event the existing engine is carbureted, or you wish to convert to carburetion (quite simple), any 1977-79 Cadillac 425 from a RWD application would work. FWD versions have a different oil pan and manifolds, as would be the case for a 1968-1974 Cadillac 472 or a 1970-1976 Cadillac 500. Basically, you could get it working, without the hassle of adapting engine accessories, by using a 472/500/425/368 Cadillac V8 from 1968-1981 (plus a limited number of 1982-84 models with the 368).

One could deviate from originality even further (dictated by convenience!) by using any drivetrain from a 1977-1996 RWD B/C/D car, adapt or transplant some of the accessories, change the transmission cross-member, and adapt the driveshaft as required, and so forth. The later fuel-injected engines entail the added complication of swapping manifolds or adapting EFI wiring harnesses, and ensuring the fuel system is compatible (SPFI require a higher operating fuel pressure).

Bottom-end failure on these engines is extremely rare. Given the typical use of such vehicles, carbon build-up is always an issue; a piece of carbon in the squish area could cause a knocking sound under all conditions, which can be fixed by some combustion chamber cleaner and spirited driving. Does the knocking change with load? Exhaust leaks typically get quieter once the manifold warms up. 368s tend to have a problem with loose exhaust manifold bolts.

Thanks for all the info I will pass this on to the mechanic. The noise use to be softer and only after the car warms up. Now we have changed the oil to 0/30?? oil as winter is approaching here and it is louder and the noise starts almost immediately when you start the car.

I have only put 250kms on it in the past 3 months.

When you step on the gas to move the noise lessons but I do not know if the noise stops or the engine is louder and I cannot hear the noise anymore. I drove the car the other day to deliver remains to a small community and it ran PERFECT except for the noise. My husband says the noise stops when under load but I don't really know.

My mechanic said he put some kind of oil in just to try to see if the noise lessened...the oil was really really thick....actually you had to heat it up before you put it in but the noise never stopped.

Also my mechanic could not find the wires for the 4-6-8 set up so he was thinking it wasn't one of those engines even tho we were told it was.

Thanks again

[steve6]

Question to you all .......the 8 6 4 engine in my hearse was only in production for 1 year....very very hard to get....imposible here in the Canadian Arctic, what I need to know is (this might be a real tough one) but what other engines would fit in this chassis if any??

heh its odd you mention that, my dad just bought a 81 deville with the BB in it, the 8,6,4, in southern ontario area, it was a southern car that has been in canada for a long time now, and it runs great!

[nwtnan]

Well.......here is an update!!

THE HEARSE IS FIXED AND WAS USED AT A FUNERAL YESTERDAY!!!! It ran awesome!!

Pulled out the old engine and shipped it 1500kms to the nearest shop that could handle a rebuild!

They bored out the cylinders, new pistons and rods, machined the crank shaft and sent it back up to Yellowknife. NO MORE TICKING!!

When the mechanic here pulled the top end off, the pistons and rods were out of speck badly!! There is no shop in this town to handle this work so it had to be shipped out!

It was off the road for about 6 weeks as they had to wait on parts.

You should hear this hearse purr now......sounds like a muscle car!! Great for funerals LOL!

Thanks again everyone for all your help!!

Cheers

Joanne

[BodybyFisher]

Congratulations Joanne, glad you got her fixed up... Good Luck

[Bruce Nunnally]

Thanks for keeping us posted. Glad to hear a happy ending.