Hey all, I've had the Poncho parked for a while since I've been traveling for work. Just got back and fired it up, and all of the sudden have 2 new engine noises that I've never heard before. First started a high pitched whining noise, which I immediately thought to be either belts or vacuum leak. I've checked the belts, tried lubing them and double checked tension - it's not the belts. So I'm guessing that high pitch whine is a vacuum hose somewhere, I'm still tracking them down and checking for cracks. Any other ideas? Second, after running for a bit, this knocking noise started and is getting louder and louder. Increases with RPM (just like the whine). It may sort of sound like exhaust leak on the video, but it's not that, it's definitely an internal engine noise. Any ideas on what this might be? Any help or ideas is appreciated!
Man it's hard to tell on my little computer speakers. I know it's a weird question but are you running a mechanical fuel pump?
The whine could be the water pump and the knock. I had a bad water pump on the '57 after a long winters rest! Take the belts of and run for a very short time and see if the noise goes away. Could also be the P.S. pump. Good Luck KK
Sounds like a loose rocker arm to me.The whine I couldn't hear but I would check the trans fluid level;they can make some strange whining sounds.
@Saxman - yes, original mechanical fuel pump. Never yet had an issue with it. How can I tell if it's the issue? @koolkat - could possibly be water pump. I resurfaced the water pump housing when i put in the new radiator and went through the cooling system. It was in good shape at the time (few years ago), so I kept it in. So if i took the belts off and quickly ran it, if there was no noise, would this isolate the issue to the water pump? @safariknut - the trans was just rebuilt last year, it's full up on fluid. Not familiar with a loose rocker arm, but will look into this too.
Take belts off,See if it stops. I'm kinda thinking alt. or power steering pump. Stick a screw driver in you ear and hold it to a few areas and you'll be amazed at what you'll hear. Also check your fluids. I had a Pontiac just like this one and if it was like a quart of oil valve train would start making some weird noises. Happened at the agriculture stop heading into So Cal. from Vegas in the middle of the night.Topped off oil and all went away Whew thank God.
@yruhot - it was low on oil. I added a half a qt, but going to add a bit more and see if it improves...
If it has a vacuum pump made in the fuel pump could be a bad hose there. As stated before get a long screwdriver and rap the knuckle of your thumb around the the end of the handle and put your knuckle on the the little flap buy your ear ho;e and fold the into your ear hole gently (you can play with that to see what gives you the best sound) and place the other end of the screwdriver against stuff that that is not moving.
I had a similar noise in my 55 Safari but the noise was only present at idle and went away as soon as the revs came up a bit.Changed just about everything on the front of the motor until I discovered the vibration damper rubber had disintegrated.Replaced the crank pulley and the sound was gone. Also had a couple of rocker balls go bad and that noise(metal on metal)got louder as the revs increased.Replaced them and it was fine. A TIP: If you have to replace the rocker balls get some clips to keep the rockers from spraying oil everywhere when you adjust them.You only need to take a bath in hot oil ONCE!
So I was doing some more troubleshooting yesterday, and double checked the belts. I noticed that my alternator was adjusted all the way out and now there was a little more play in that belt than I wanted to see. I'm replacing that belt to see if it could possibly be worn past the point where I can adjust out the alternator to get rid of the slack. I'm hoping its just actually this belt rather than something more complicated!
To follow up, the issue was caused by me using an OLD (Vulco V-Belt from the 1950's) belt on the alternator. It was worn out and had too much stretch in it. I replaced with a new belt, and that seems to have resolved it!
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