Ticking noise - tied to engine speed - phenolic odor

Hello all - got my E-type back from the shop Friday and took her for a couple jaunts yesterday. It was wonderful to have her on the road again and the New Hampshire back roads with their corkscrews and ups and downs did not disappoint. During the second ride with my ladywife along, we noticed a funny “hot” smell. Not incinerating wires, but faint and slightly concerning - thought it was the clutch after a hillside start at a stop sign, but it came and went with the windows open. As we got back into our town, a ticking noise started, like a small fan blade on metal but fainter - rose and fell with revs. I pulled her in the garage and opened the bonnet. no apparent rotating things hitting non-rotating things - water pump seemed tight - dynamo seemed alright - and the belt was very tight. Started it again and tried to track the noise - seemed to come from the front of the engine (water pump/dynamo territory) but I couldn’t rule out the front of the engine itself and thoughts of chain tensioner disintegrating set my to worrying hard. We replaced the harmonic balancer (this was a “needs a lift” shop visit), that had disintigrating rubber (SNG), and the fan belt (XKS that I carried as a spare) The old belt was not as tight, and the new one was very tight. My son and I tried to take the belt off last night and stopped to reconnoiter again this morning - the thought was to start the car without the belt and see if the noise still existed (eliminating the water pump and dynamo). We set to thinking about it and I know I overtightened some fan belts in my youth, costing me a couple alternators before I wised up - but there was never any smell, just a lack of charge and rumbling of the shot bushings. We have reasoned that the water pump is tight, and the smell may have been phenolic resins used in the windings of the dynamo - but I’m not sure they have such material in the windings or elsewhere on the dynamo. I didn’t lay hands on the dyno, but she was pretty warm as was the entire engine.

Has anyone gone through a cam chain tensioner failures and would the engine have cratered by now if that had happened (god forbid)? Also - could the change in harmonic dampener have increased the length double-vee belt needed - have there been issues with short belts from suppliers? and how does one dial in more play in the belt (only moved up and down 1/8")? Sorry for all the details, I’ve left out the good parts of the drives and zooming around the twists and turns… all the best, Pete

This might not be the cause on your car but on my '68 S1.5 I had the exact same noise and it turned out to be the alternator fan touch the water overflow hose (which I have clamped to the top of the rail. I had removed the automatic belt tensioner causing the the alternator position to take up the belt slack…it had to be moved too far…replaced the auto tensioner an all was well. The fan had almost cut through the hose and it had to be replaced.

I am confused if you have ruled out the alternator or not ? Last year I had a rebuilt Delco start to come apart about 15 miles after I installed it. It was not subtle though and obviously the alternator since in my case the rear plug for the rotor shaft had fallen out and was screeching loudly. I was lucky that it did not grenade on me at 60 MPH. On my E it is easy to remove the belt.

David
68 E-type FHC

there doesn’t seem to be anything hitting another item - Should probably have noted my car is a '64 FHC with all the trimmings of positive earth, dyno, etc. The belt is very tight…and I am hoping it is belt related and not engine internals related…

The Dyno has worked alright for the past year ~1100 miles - my thought is with the belt and/or harmonic dampener change the system got too tight…

I have and would say the sound was more noticeable than you describe and distinctive enough that I was pretty sure what had happened even before I opened the bonnet. I’ll add that you can drive many hundreds of miles with the usual failed tensioner (leaves on metal on metal) so no immediate disaster.

Certainly running briefly w/o the belt(s) is a first step in tracking a noise. Also useful may be a mechanics stethoscope (or a long screwdriver) to ascertain if there is untoward internal engine noise.

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I had a rattling mechanic noise at the front if the engine last summer. I suspected the generator, valves, tensioner and water pump. Turned out to be much easier… a blown gasket at the front exhaust manifold.

It is wonderful having this forum and other forums out there - found a string on another forum talking about short belts. Apparently the length needed is 1010mm to 1020 mm depending on model - SNG has the 1010mm and they are right up the road. I got the one on the car from another supplier out west - it measures 1003mm and the tensioning pulley is pushed all the way in - and tighter than a fat man’s sock. The prescribed 1/2" up and down slack in the belt is not to be found - and the most I can get is 1/8"…not sure what the condition of the generator is at this point. water pump is dry so no big failure there.

The ticking is rapid - like playing card in bicycle spokes (1960’s kid’s Harley wannabe) - so it isn’t like a valve click or such. Since SNG is just up the road, I may cut the belt off and see what’s up - if the tic ck is still there. It is not a metal on metal sound - the engine was rebuilt - so hopefully it is external to the engine. Such a wonderful pair of drives yesterday…

Given the scope of work you describe I doubt something has gone horribly wrong inside your engine.

Is something hitting your new harmonic balancer? The timing marker perhaps? You don’t say what series you have, but it is possible for the HB to touch the bottom radiator hose in the 3.8, and I have had one cut into it and dump the coolant.

You’re correct about the replacement fan belt being too short. One solution if you can’t get the 1020mm belt is to remove the tensioner (a frequent source of noise) and tension your short belt in the normal fashion using the alternator.

Sorry - mixing units here - the belt on there is 1010mm. I think this one usually goes with cars that do not have the Jockey pulley. Not sure though.

Yes - I am going to go after this after visiting the tax person today…The normal adjusting bracket on the Dynamo (slot with adjustment bolt) is not there - just a hole (no slide adjustment) - probably because of the pulley tensioner (which is fully pushed in because of the short belt.). There is a string on another forum that mentions a belt: C24291 that is a duplex belt 1100mm long. May try that too.

I would suggest you cut a piece of hose to about 4 feet long.
Put one end to your ear and use the other end to hunt for the source of the noise.

I have used this many times to isolate the source of a noise. The last time I did this, it turned out the be the front alternator bearing.

Dennis 69 OTS

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Anyone who works on cars should have one of these. Really amazing. You can work your way along the cam covers and listen to individual bearings.
https://www.amazon.com/Lisle-52500-Mechanics-Stethoscope/dp/B0002SQYSM

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Sometimes it is the most mundane of things. I noticed a ticking sound, engine revs related, drinking to see Dad just over a year ago. I stopped, and discovered the fan belt was disintegrating, a wire from inside the belt was free abusing the ticking sound. As I always carry a spare belt and basic tools, the suspect belt was replaced and we went on our way.

It turns out the belt had been miss labelled as suitable for an E-Type. It wasn’t. It was too deep a profile for the pulleys on the E-Type. The replacement was correct. It is the only fan belt failure I have ever had in 47 years of motoring.

I hope it was a closed container :slight_smile:

Sometimes the most mundane of things becomes something quite different, for example when predictive text changes what you are doing. I suppose a 2+2 could be described as a closed container. But I wouldn’t want to drink out of one.

And besides, today is the day I drink my car to see Dad for the first time since lockdown. Looking forward to that.

I will check again - the access is limited (on my knees, crushed into thew wheel arch of the bonnet and cantilevered into the engine bay - the E-Type position in Yoga…) and I always forget to bring something into the engine bay with me, repeatedly…I’ll have a firkel about and feel for disintegrating belt, reconnoiter the jockey pulley, and the rest. I may go with the 1100mm belt, and an adjustable bracket for the dynamo - assuming the bearings aren’t shot. I killed a couple alternators in my youth over-tightening the belt on an MGB…the old adage “tight’s tight, too tight’s busted” never rang so true…

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Well the culprit is the Dynamo, because of the tight belt. The bearings cratered. I was able to start the engine and lay a hand on the dyno while it was running, and bingo - it was rattling hard like marbles in a tin can. This explains the phenolic smell (like a 12-volt transformer for your train set when you ran it until it got hot…) and the fact that it started faint and kept getting louder. Glad it was nothing internal.

It seems that not all parts are alike - replacements may be short (mine was the prescribed 1010mm) - but when SNG checked the 1100mm belt they said it is listed for my car - despite the search for a belt using my car input to the system pointed me to the 1010 mm belt. I have ordered the 1100 mm belt, an adjustable dyno bracket, and we will install the dynalite alternator I bought last fall. Sorry to crater a perfectly good dynamo though. May rebuild it anyway to see if it can be done… Thanks for the suggestions - I would have laid a hand on the dyno earlier, but it was at broiling temp like the rest of the engine…

The 1100mm belt is C24291 - that is listed for a MK2 3.8S and E-Type. There is a 1050mm belt (C19525) and the C19524 that is the 1010mm belt. With the 1010mm belt the jockey pulley was completely compressed, and the non-adjustable dyno link made the belt extremely tight. Found the different belts on a British Forum that popped up with a search - thankfully - as well as a discussion on the older belts that had a canvas-like finish on the outer side and review of how the two duplex “v’s” should seat into the pulleys and not ride proud.
all the best, Pete

One last edit - the 1100mm belt is a bit too long…so it will end up with the 1050mm belt (C19525) - who says trial and error doesn’t work? (but it can be expensive…)

It would be nice to have a spare if you can get bearings and they don’t cost more than a replace alternator.

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Thats where a stethoscope/long screwdriverwould have been useful early on.

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