Engine Squeel part 2

[Ron67Alpine]

Not long ago I posted a couple of questions about water from my exhaust and a squeal coming from engine.
I've come across a factory service bulletin posted on TE/AE forum site that may be pertainant.
Bulletin 68-18: Alpine V Engine Vibration:
http://teae.org/1968/bulletin-68-18/
This is about a "vibration" particularly around 3200rpm which can be "felt" through the gas pedal. It is apparantly associated w/the center exhaust manifold bolt.
Has anyone ever had this problem and is there any kind of noise or squeal associated w/this vibration? This question is only about wether the above "vibration" talked about in this service bulletin can generate the squealing, I've been hearing. Suggestions from the previous threads have included belts/alt/water pump, #3 rod bearing, something dragging on the flywheel, starter not disengaging, distributor bushings, rear main bearing, center main journal thrust bearing. The simple stuff I've taken care of, I'd really like to totally eliminate all the easy stuff, before I take the engine apart or buy new distributor.
thanks,
Ron
Below are some quotes, from the "water from exhaust" thread discribing what I'm hearing and where it's apparantly coming from.

"When I go quickly to a high rpm, I hear a screeching. I'd, previously, thought it was the pump or belt, but I've fixed those things. "
"The screeching is a worry, I was also thinking of a spun bearing. I've got around 22lbs oil pressure @ around 2K rpm, 40 @ 3K. I've got a new aftermarket OP guage."
"I kinda included eliminating anything associated w/the belt/alt/waterpump, when I mentioned replacing WP/belt. It was also the first thing I thought of when I got it started the first time and heard the noise. The alt is also a new replacement. Everything up there is now quiet as a church mouse."
"I've been hearing this racing idle screech, since I first got the engine running, last spring. As mentioned, I've pretty much gone down the list of standard suspects. Alt/pump/belts are all new and not making any noise. There was quite a bit of time while waiting for parts to arrive, where I did start the engine w/everything disconnedted from the belt and still got the screeching, when engine races."
"I'm pretty sure the starter is disengaging. I've had no problems w/jamming. It's not a clattering of gears grinding, either.
Since, getting it to idle, relatively well, I've been able to listen better, as to where it's coming from. It's not as loud as it used to be and seems to be coming from mid engine, under the manifolds. It only happens when, it (quickly) revs from low to high rpms. It could even be metal on metal vibration."
"I replaced it w/a new steel pump from Classic Sunbeam as well as a new alternator. I also heard the noise at least once, when I had the alt and WP removed while waiting for replacements. I know this sounds like one of the above but I'm really sure it's not."
"I was just in the garage, idling the car. I had her up to over 5Krpm before the screaching started."

Since my last post in the "water" thread, I've done a couple of more tests w/engine speed. If I slowly bring the revs up, it doesn't squeel, until reaching around 5K, but if I quickly bring the revs up, it starts at a much lower rpm. Pushing the clutch in while squeeling does nothing.

 

[mikephillips]

The only noise like that I can think of that a problem bolt might cause would be if allowed an air leak into the joint, that could possibly cause something like a whistling sound. But, when it started and it's progression as engine speed increased wouldn't be dependent on how fast you opened the throttle. And you probably notice rough idling since at low speeds the air imbalance would be more of a problem. So after all that I'd have to say it's unlikely to be related.

 

[Ron67Alpine]

Thanks Mike, it's definately not an air shreek. What I was thinking about is vibration, at certain rpms, between the flat parts of the clamp and manifold causing the squeal. When I get down close to where it's coming from, I sometimes think it's a flat metal on flat metal kind of noise rather than rotation noise.
Ron

 

[MikeH]

I had a squeal coming from my MGB. It ended up being loose intake bolts. The gasket acted as a reed and made the noise. It took quite a while on google to find an answer and that tuned out to be the cause on the MGB

 

[RootesRooter]

One more time: remove the fan belt to get a better idea of where the noise is or isn't coming from.

Maybe it was just my cheap speakers, but your engine didn't sound very good in the "First Time" clip even before the squealing started. Is the exhaust system hooked up and intact? The squealing sounded like a rotational scraping.

 

[Tom H]

Ron,

Regarding the tech note, it does not seem very applicable since you are not using a SV manifold.

But MikeH 's experience may suggest a similar issue. So it should be pretty easy to just tighten up the manifold bolts a bit and see if that solves it.

But I'm mostly in RootesRooter's camp and think it's really a rotational scraping sound. Very easy next step in my mind is to pull the flywheel inspection plate. Just a couple bolts to remove it. You can even keep the block support struts in place and reinstall the bolts that hold them to the bellhousing. You might see some scraping evidence on the plate. or you may see something there. From the sounds you recorded, I did not think it RPM related. It was not something "resonant" that comes and goes as the speed changes. Those kind of resonant effects will usually 'wow' in and out smoothly as speed goes in and out of resonance. I think the screetching is only secondarily related to speed. Something like the crank moving forward or backward slightly - thousandths of an inch- as speed, temperature, etc change causes it to come in and out.

Tom

 

[sunbby]

Not long ago I posted a couple of questions about water from my exhaust and a squeel coming from engine.

Bulletin 68-18: Alpine V Engine Vibration:
http://teae.org/1968/bulletin-68-18/
This is about a "vibration" particularly around 3200rpm which can be "felt" through the gas pedal. It is apparantly associated w/the center exhaust manifold bolt.

I don't think this would be the cause of your squeal. I think my car exhibits this, but it is due to not having the rubber grommets holding the rod for the carb linkage. At certain rpms when I have it at neutral throttle, I get a high pitched rattling sound. I'm pretty sure it is the linkage rattling against the slot in the accelerator pedal. I need to fix it, as it is very annoying on long freeway trips, where you go neutral throttle at the rpm range quite often...

I agree with the other guesses about some type of rotational sound. To me it sounds like an electrical motor bearing (like the alternator) or something else of similar size, but I have no idea what it would be. I second RootesRooter's suggestion to remove the fan belt again and try it.

 

[Hillman]

I was on a road trip last summer and my SII/1725 developed a "noise" above 3000 RPM. After much searching it turned out that it was a vibration coming from the aftermarket chrome cover on the oil filter. Thew it in the trunk, problem solved. Got one of those?

 

[Ron67Alpine]

One more time: remove the fan belt to get a better idea of where the noise is or isn't coming from.

Maybe it was just my cheap speakers, but your engine didn't sound very good in the "First Time" clip even before the squealing started. Is the exhaust system hooked up and intact? The squealing sounded like a rotational scraping.

Hi RootesRooter, as I've mentioned several times, I've already had the new belt, new alternator, and new water pump off, while running, and still had the squeal. The exhaust is hooked up and intact, but I may have to retighten it @ the manifold. Your are correct that I don't have everything totally smoothed out in the engine adjustments, but I have made some progress on quieting it down, since I posted that clip. It also wasn't warmed when I made that "first time" clip. I'm idling around 1000rpm and when warm is considerably quieter. I have verified that it seems to be coming from somewhere under the manifolds, mid engine. It is definately not coming from the front.
I mentioned in the other thread that I'm getting some "bounce" on the timing mark, while using the timing light. Which, I thought, made the distributor bearing theory a possibility, but didn't get any corroboration as to what would cause timing mark "bounce". It is still running a little rough and I do need to readjust the valves. Although a rotational squeel is still a definate possibility, to my ear, there may be a bit of vibration rubbing component to the sound
Thanks for the reply, I appriciate it.
Ron

 

[Ron67Alpine]

I was on a road trip last summer and my SII/1725 developed a "noise" above 3000 RPM. After much searching it turned out that it was a vibration coming from the aftermarket chrome cover on the oil filter. Thew it in the trunk, problem solved. Got one of those?

Thanks Hillman, but no cigar and no chrome oil filter cover, either.

 

[V6 JOSE]

Hi Ron,

Have you removed the rocker cover to see that the rockerts aren´t dry. One of my customers had squealing from the engine, and when he removed the rocker cover, he discovered that the top end wasn´t oiling at all, and the rockers were blue from the heat generated with the friction on the rocker shaft.

Jose

 

[Ron67Alpine]

Thanks, everyone, you have answered the main point of this question/post. The service bulletin I quoted, has nothing to do w/my noise.
Tom and Mike (H), since I have had both manifolds off, I may not have torqued them correctly. I don't remember if I could actually find torque values, for the manifolds, in my manual. I will check it.
Guys, I apologize if, it seems, I'm not listening to your suggestions. I am listening, as well as hearing, what y'all are saying. I'm really trying to collect possibilities so I can run them down all at once, rather than checking one thing, finding out it's not the problem, then coming back and asking again. There are still things I have to tackle, before this becomes a real issue, so I'll work on those and come back to the noise when I have to.
I really do appriciate all your help.
Thanks
Ron
Anyone in the Baltimore MD area, that would want to make a house call, to straighten this neophyte out?

 

[Tom H]

Ron,

You've had 2 suggestions ( me and Chuck Ingram) to remove the bell housing inspection plate and have not yet done so. It's easy. No oil to drain, no seals or gaskets to replace. Might show something. It's gonna be pretty interesting when you finally get to the bottom of this!
Tom

 

[Ron67Alpine]

Well, Tom, I just got it back up on the stands, and I'll be sure to check out the inspection plate. I gotta say, though, it really doesn't sound like it's coming from the bell housing. I've been wrong before, and I'll be wrong again. I may be a neophyte about LBC's but I've kept junkers on the road, and have pretty good general backyard mechanics skills. They may be a bit rusty, but I think the sound of something draging on the flywheel, would not sound like what I'm hearing. Eventually I'll also remove the oil pan and check for metal. I've wanted to avoid this as long as possible, because right now, it ain't leaking, and I really dred replacing that split gasket. Anyway, I've got a long winter to figure it out and get her ready for spring...I'm just impatient
Thanks, for the help.
Ron

 

[Ron67Alpine]

Hi Ron,

Have you removed the rocker cover to see that the rockerts aren´t dry. One of my customers had squealing from the engine, and when he removed the rocker cover, he discovered that the top end wasn´t oiling at all, and the rockers were blue from the heat generated with the friction on the rocker shaft.

Jose

Hey Jose,
Do you mean the valve cover? I have removed that, semi adjusted the valves and gave it a lookover while running. To me it looks as if there should be more splatter going on, but nothing looks "dry". I do need to, eventually, replace the valve train T o-rings.
Ron

 

[Tom H]

Ron, you say you'll need to "replace" the o-rings in the oil T fitting?? Did you put some in there? Understand that there are/were not any there originally. Many of us have added them, but it's not stock.

Tom

 

[Ron67Alpine]

Tom, here is where my ignorance of the LBC's will show. I earlier put up a post about, what I thought was, a seeming low amount of oil in the valve cover. One of the bits of information, was to check out leaking around the T and replace the o-ring, if excessive leakage. Sorry, I forget which member told me about it . So to answer your question, I have no idea whether there are o-rings in there or not. Which I guess, brings up another question. If there were/are none there, stock, what size am I gonna need?
Like I said, I know I still have some engine things to take care of. When I got this project I concentrated on just proving the engine could run. My prior experience indicated if it ran, it was just a matter of dialing it in. I then concentrated on getting the rest together. I naively though I'd have a runner by spring...ha, ha. I've just never worked on something that has set for so long, and knowing little about it's history. Of course, I'd like to get away w/o doing major or even semimajor engine work. Well, now I have another winter to work out these engine bugs. I'd still prefer to have some idea of what I have to look forward to, w/o doing an entire rebuild.
I'm so close to get her back on the road, I'm just impatient.
Thanks
Ron

 

[RootesRooter]

You may be able to further isolate the noise by holding a length of rubber hose up to the engine and listening at the other end.

Did you try engaging the clutch during the squealing? (i.e. broken clutch spring).

 

[Ron67Alpine]

You may be able to further isolate the noise by holding a length of rubber hose up to the engine and listening at the other end.

Did you try engaging the clutch during the squealing? (i.e. broken clutch spring).

Yeah, I know RootesRooter. I just have no one around, I can get to help w/things like hold the accelerator or pump the brakes. I'm pretty much working alone, and basically have to wait until a friend stops over, at the right time.
I did engage the clutch while squealing. There was no appriciable change or possibly a very slight drop in rpm but the squeal did not change.

 

[MikeH]

It doesn't have to be a tube or hose, you can do the same with a long screwdriver.