Need advice. Tappet sound

Fishfan

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Here's the deal. Last week I had an issue with the carburetor on my 318 Poly. I took the advice of the guys on the board (thank you, by the way) I decided to have the original Stromberg carb rebuilt rather than fixing the Holley that was on the car and was shooting fuel out of the vent tube.

The car was at the mechanic's where I had had it towed when the carb problem sprung up. I brought him the rebuilt Stromberg and had him install it and do a couple of other jobs I needed to have done (rear axle bearings needed replacing and I had him install an electric pusher fan I had bought and was planning to install myself).

The car was in the shop a week so I was anxious to get it back. Today he called and told me there was an issue with the carburetor. He thinks there's something wrong with the accelerator pump. I asked if the car was drivable, figuring I could take it to the guy who rebuilt the carb in the morning. He said it was drivable but it'll want to die on you if you give it gas too hard, etc.

The mechanic was closing up shop when I picked up the car. We talked about it a while and then I left. The acceleration out of idle was just as he described it but then I started hearing a strange tapping or sound from the engine compartment. When I got it to my office it sounded like it was coming from the driver's side valve assembly. Note this engine was rebuilt in 2007 and has approximately 5000 miles on it since.

So here's the questions. Is this car safe to drive to my home (approximately 15 miles away) with this tapping noise?

What might be causing this?

Could fuel delivery because of the unresolved carburetor issue be the cause?

I will call mechanic in the morning to get his take on it but right now it's after hours.
 
You're probably fine to drive home. If it's stumbling off the line I'd look for a vacuum leak or perhaps he hooked vacuum advance to the wrong port. lean condition from a leak could cause print ion but I doubt it. Might just simply be a stuck lifter. Sort the carb issue first then tackle the tappet noise.
 
When the holley carb was acting up how much fuel if any went into the crankcase? Ck the oil and see if it's too thin (oil diluted)
 
When the holley carb was acting up how much fuel if any went into the crankcase? Ck the oil and see if it's too thin (oil diluted)

Winner winner chicken dinner!

So I went down to the car and checked the oil. I smelled the dipstick and it was high octane. I decided to go to the local O'Pepadvancezone to get some new oil and a receptacle. As I drove there the noise got much worse. Both valve assemblies seemed to be rattling like mothers (which is different than the original intermittent clacking that I heard on the way to the office). I got the oil and took everything back to the office garage and changed the oil. I'm going to have to do it again because I didn't change the filter so I figure there's a quart of contaminated oil still in the system.

The noises didn't go away right away but by the time I had driven a couple of miles and got it up to highway speed most of clatter had disappeared and only the original intermittent clacking remained. Still worried about that.

Thanks so much 65sporty.
 
After you change the oil one more time, a can of STP or some other gooey stuff should help quiet things further.

Posted via Topify on Android
 
The gas will also boil off. If you have most of the oil changed, keep your eye on the dipstick level. You might see it go down as the volatile gasoline evaporates under the heat of a running engine.
 
So I haven't had a chance to take the car to the guy who rebuilt the carb and won't have have time until next week but it looks like the problem is with the accelerator pump. I think it's stuck.
 
After you change the oil one more time, a can of STP or some other gooey stuff should help quiet things further.

Posted via Topify on Android

Thanks for the tip. Worked like a dream. Carb guy found some issues in the ignition system. Everything running great now and no more tappet sounds.
 
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