Need Some Validation

[Scotty]

I drive this car daily and I'm trying to keep it that way.

So I've been fouling plugs like mad and have had gas flooding the car, so I redid my Weber. Adjusted the float to spec (it was off by quite abit), changed the oil, plugs, etc. My adjustment went from 1-3/4 to 2 turns on mixture.

I have a Series IV, 1725, Weber (32/36, Mixture out 2-1/4, Idle in 1-1/2). Running Shell Rotella 15-40W, Autolite Irridium XP63 plugs and electronic points made for the 25D distributor.

Before I had either a hard time or easy time starting it. Now it starts right up. It idles at 850. Here's a video of it running. I'm still doing some wiring and organizing things better, so please don't get on my case about it, I know, I know. I just want to know if it sounds right or if there's something else I need to adjust. The metal mesh vibrating sound you hear is from the ram flow mesh on the Weber and the exhaust is dirty and the metal makes it look worse. It vibrates a little bit but I've been told that's supposedly normal. I keep thinking the vibration is either normal or the motor mounts are too stiff. They were bought from SS when the engine was dropped in this car back when the engine was rebuilt.

While I have seen and heard a few Tigers, I have never seen or heard another Alpine in person and I have little idle how they sound like in person and I'm incredibly paranoid with trying to take care of this one.

How does it look and sound?

Video Link: https://streamable.com/izdlle

 

[alpine_64]

Scotty. That sounds like an alpine! One thing i would note is that you say the idle is at 850rpm, to me that sounds higher in your video.

 

[Scotty]

Scotty. That sounds like an alpine! One thing i would note is that you say the idle is at 850rpm, to me that sounds higher in your video.

That what has me going too! I keep feeling like it's really loud at idle. It's absolutely at 850, I'm using a quality Tach to test it to make sure the RPMs are accurate. I'm not sure what it could be and I've gone so far as to do a block test to make sure I didn't blow the head gasket.

Is that vibration normal for these engines?

I recorded this on my Iphone using its mic so the quality is really clear.

 

[husky drvr]

So I've been fouling plugs like mad and have had gas flooding the car, so I redid my Weber. Adjusted the float to spec (it was off by quite a bit), changed the oil, plugs, etc. My adjustment went from 1-3/4 to 2 turns on mixture.

I have a Series IV, 1725, Weber (32/36, Mixture out 2-1/4, Idle in 1-1/2). Running Shell Rotella 15-40W and Autolite Irridium XP63 plugs.

Scotty,

Just a couple of thoughts. I've read articles where new carbs (not Webers) have been ordered, delivered, had some issue when running, pulled and torn down, or a preemptive tear down and check was made which discovered a very out of spec float setting. Think most were attributed to rough handling during shipping as the most likely cause. Think that might be your gotcha?

Next, I'll agree with Michael on the idle speed "sounding" too high. If as you state you are using a quality test tach, not the car's tach, is it set for use with a four cylinder engine? If set for a six cylinder test, your idle would be closer to 1275 RPM. I recall when approaching that low an idle, the engines always had an irregular miss, called "hunting," attributed to weak sparks and poor mixtures. With your aftermarket ignition and iridium plugs, you shouldn't have that happening.

On your mixture and idle settings, are those the actual measurements, or the change from where you had them set previously? Your settings don't look to be very far from baseline, if actual. Next questions are ignition settings and vacuum advance as checked at your idle, and static.

In engineering terms, all inline four cylinder engines have a neutral primary balance because the crankshaft design always has two piston/rod assemblies countering the other two assemblies during rotation. The catch is inline fours have a distinct secondary IMBALANCE that is at a frequency TWICE the speed of crank rotation. The base cause of secondary vibrations are piston speeds and rod angularity not being a match in the up to down traveling pistons. High mass pistons and rods play a part also because the piston/rod assemblies accelerate from stop to max speed to stop TWICE every crank rotation. The proper cure is the use of balance shafts. Mounts are only a band-aid, at best. Even the original engine mounts transmitted a lot of that vibration into the body.

Just stuff to think over,

 

[Scotty]

Scotty,

Just a couple of thoughts. I've read articles where new carbs (not Webers) have been ordered, delivered, had some issue when running, pulled and torn down, or a preemptive tear down and check was made which discovered a very out of spec float setting. Think most were attributed to rough handling during shipping as the most likely cause. Think that might be your gotcha?

Next, I'll agree with Michael on the idle speed "sounding" too high. If as you state you are using a quality test tach, not the car's tach, is it set for use with a four cylinder engine? If set for a six cylinder test, your idle would be closer to 1275 RPM. I recall when approaching that low an idle, the engines always had an irregular miss, called "hunting," attributed to weak sparks and poor mixtures. With your aftermarket ignition and iridium plugs, you shouldn't have that happening.

On your mixture and idle settings, are those the actual measurements, or the change from where you had them set previously? Your settings don't look to be very far from baseline, if actual. Next questions are ignition settings and vacuum advance as checked at your idle, and static.

In engineering terms, all inline four cylinder engines have a neutral primary balance because the crankshaft design always has two piston/rod assemblies countering the other two assemblies during rotation. The catch is inline fours have a distinct secondary IMBALANCE that is at a frequency TWICE the speed of crank rotation. The base cause of secondary vibrations are piston speeds and rod angularity not being a match in the up to down traveling pistons. High mass pistons and rods play a part also because the piston/rod assemblies accelerate from stop to max speed to stop TWICE every crank rotation. The proper cure is the use of balance shafts. Mounts are only a band-aid, at best. Even the original engine mounts transmitted a lot of that vibration into the body.

Just stuff to think over,

The Tach I'm using to test is set to 4 cylinders and is reliable. It reads 850 but it does sound loud and that kind of annoys me. My car has always sounded loud.

I think the gotcha was the float because it was ridiculously out of spec. I reset the float to what the Redline Weber 32/36 is supposed to be and it cleared up a LOT. I leaned it back and it went from having some issues starting to now firing up almost immediately. My previous setting were 1-3/4 mixture and 1-3/4 idle. My current setting is 2-1/4 mixture and 1-1/2 idle. My ignition timing is 8 degrees BTDC. I'm not currently running vacuum advance. Trying to really understand it before I start messing with it.

Ah, ok. So a little vibration is perfectly normal, then. I was kind of freaking out about that.

I feel stupid right now. Is there something really obvious I am missing or am I being really paranoid?

 

[alpine_64]

The Tach I'm using to test is set to 4 cylinders and is reliable. It reads 850 but it does sound loud and that kind of annoys me. My car has always sounded loud.


Ah, ok. So a little vibration is perfectly normal, then. I was kind of freaking out about that.

1. It's not how loud that makes me think the car is idling faster it's the speed it's ticking over.. 850 the cars sound a bit slower and loppy.

2. Many of the new engine mounts have rubber that is to hard and creates increased harshness and vibration as they don't isolate enough.

 

[hartmandm]

Motor mounts - what Michael said - many are too hard.

Back in 2015 I installed an overdrive gearbox. At the same time I installed new motor mounts purchased from Curt at Classic Sunbeam and gearbox mounts from Rick at SS. The whole car vibrated and rattled like heck with the new motor mounts. I called Rick at SS looking to source replacement mounts and he told me the rubber on his motor mounts was too hard as well. I ended up sourcing good motor mounts from Rootes Parts Service in the Netherlands. So unless Rick received an updated batch of motor mounts with better rubber, I'd assume he is still selling motor mounts with rubber that is too hard.

The new gearbox mounts from SS seemed ok, as I didn't replace those and the car was back to normal once the good motor mounts from Rootes Parts Service were installed. I could get an idea of the rubber hardness just by squeezing the rubber in my hand. The gearbox mounts rubber seemed soft.

Mike

 

[Acollin]

Sorry for being so thick, but I have lost track of your concerns.
after reading the thread, it sounds like fouling plugs is no longer an issue. Idle is questionable— it does not sound like 850 to me but if you have confidence in your gauge— you have confidence in your gauge. That said, I prefer my idle a bit higher 900-950 ( not your problem!!)

I would, however, check my tach on another car simply to verify or borrow another tach ( auto parts store, local mechanic, neighbor) nothing like more opinions to confirm. If your checks confirm the 850, why not lower the idle to a sound you find reasonable and do a running check— if plugs suggest neither lean or rich adjust to improve any vibration that offends you. While I too am a by the book guy, the tools we use can be compromised and unless you are running all factory original components( either on the car or mods like webers) for my thinking, it would a challenge to dial anything in in terms of the wsm or tech data from a component. I would be looking for working right ( good looking burn on plugs) and using more “feel”/ “intuition”.

As I said up front, I am not really sure what you hope to achieve— not being critical, just trying to better understand.
be well
Andrew
would a sounds / video clip of a pretty much stock 1725 series v help? I could even try to include footage of the tach I use— an old sears tach and dwell unit.

 

[Scotty]

Sorry for being so thick, but I have lost track of your concerns.
after reading the thread, it sounds like fouling plugs is no longer an issue. Idle is questionable— it does not sound like 850 to me but if you have confidence in your gauge— you have confidence in your gauge. That said, I prefer my idle a bit higher 900-950 ( not your problem!!)

I would, however, check my tach on another car simply to verify or borrow another tach ( auto parts store, local mechanic, neighbor) nothing like more opinions to confirm. If your checks confirm the 850, why not lower the idle to a sound you find reasonable and do a running check— if plugs suggest neither lean or rich adjust to improve any vibration that offends you. While I too am a by the book guy, the tools we use can be compromised and unless you are running all factory original components( either on the car or mods like webers) for my thinking, it would a challenge to dial anything in in terms of the wsm or tech data from a component. I would be looking for working right ( good looking burn on plugs) and using more “feel”/ “intuition”.

As I said up front, I am not really sure what you hope to achieve— not being critical, just trying to better understand.
be well
Andrew
would a sounds / video clip of a pretty much stock 1725 series v help? I could even try to include footage of the tach I use— an old sears tach and dwell unit.

You’re not thick, I’m just not explaining myself right. My apologies.

What I'm trying to find out is what is the right look/sound for a Alpine engine, in terms of sound and appearance. I know older cars have some or little vibration and other ones have vibration inherent in them at idle of some sort but what does an Alpine at idle look and sound like. I keep feeling like mine is wrong.

To me, my idle sound seems both loud and wrong. I'd love to hear/see what an idling Alpine sounds/looks like. While there are several on Youtube, they range from eerily quiet to super loud and vibrating like mad. I just have nothing to gauge what a "right one" sounds or looks like at idle.

Update: So I decided to unhook the other Tach and only run the one Tach hooked up, my Autozone one and it jumped up to 750 on cold start and went to 1050 at full warm up. Grr. I adjusted the idle down and enriched the mixture abit and this is where I'm at, running at about 800:

UPDATE: Updated video link:

IMG_3481

Watch "IMG_3481" on Streamable.

streamable.com

 

[Scotty]

Motor mounts - what Michael said - many are too hard.

Back in 2015 I installed an overdrive gearbox. At the same time I installed new motor mounts purchased from Curt at Classic Sunbeam and gearbox mounts from Rick at SS. The whole car vibrated and rattled like heck with the new motor mounts. I called Rick at SS looking to source replacement mounts and he told me the rubber on his motor mounts was too hard as well. I ended up sourcing good motor mounts from Rootes Parts Service in the Netherlands. So unless Rick received an updated batch of motor mounts with better rubber, I'd assume he is still selling motor mounts with rubber that is too hard.

The new gearbox mounts from SS seemed ok, as I didn't replace those and the car was back to normal once the good motor mounts from Rootes Parts Service were installed. I could get an idea of the rubber hardness just by squeezing the rubber in my hand. The gearbox mounts rubber seemed soft.

Mike

That's weird. Are the ones Rick supplies meant for anoher brand of car and they just happen to fit ours?

I'm going to order some this week, swap them in and see if it makes a difference with the vibration.

 

[hartmandm]

Rick is selling motor mounts for Alpines. Rick was unhappy with how hard the rubber was on the mounts. I think it was just a case of his supplier not providing the part with the right rubber specs. The mounts might fit other cars.

Rootes Parts Services in the Netherlands is the only supplier I know provides mounts with the right rubber softness.

Mike

 

[bobbo]

try a look at the videos on Tim's site " the Alpine channel " on youtube. I recall one of his videos had an engine running at idle with sound.
Sounded pretty noisy to me at the time.
Bob

 

[husky drvr]

Google Drive: Sign-in

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Scotty, your new video is not accessible on my ancient desktop. Any possibility of posting in another format?

HAGD,

 

[Alpine 1789]

I'd love to hear/see what an idling Alpine sounds/looks like.

Scotty: your profile says "West Coast". Where on the West Coast are you? Maybe we can find another Alpine not too far from you.

 

[husky drvr]

UPDATE: Updated video link:

Thank you for the new link. Your engine sounds like it's idling much lower now.

Congratulations,

 

[Acollin]

Hey Scotty

what happened in the vibration department with the carb adjustment? I assume there is still an issue there given you said you were planning to swap your current motor mounts out.
i could not detect any vibration that would trouble me in your video. Is your concern still as you described it initially?
car sounds good to me!!
be well
Andrew

 

[Tom H]

Scotty,

You say you "redid" your Weber 32/36 but have made no mention of the jets. Do you know the history of your Weber carb? Was it jetted appropriately for your engine? There are 4 jets on the Weber 32/36, and the wrong jets can cause problems. Primary Idle, Secondary Idle, Primary Main, and secondary Main. There are many threads on this forum with discussions about the correct jets to use.

Tom

 

[Tim R]

Scotty, Your second video sounds much better. If you dump that log inlet manifold and fit the curved one you will immediately get a lower and more powerful tick over. The log manifold will ALWAYS make two cylinders run worse than they could. Fit the curved manifold and all run equally, the improvement is massive and immediate. My car ticks over about 600 revs and will pull cleanly away from the lights with no problems see below.

Tim R