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Vintage Volvo 164 Tapping

C

christianthomas

New member
Joined
Jan 27, 2021
Hi all! I'm a volvo newbie but have always admired from afar. This summer I had the chance to scoop up a '69 164 in relatively good condition. It runs well but it has a tapping sound. I've got it into a shop but they're reticent to take it apart because they're not sure if they can get it back together depending on what's wrong with it and what parts might be available. Is there a good place to look for donor engines?

The car has (supposedly) 64,000 original miles and has been in storage the last 10 years.
 
I'd figure out the tapping before looking for donor engines. Also, donor motors for a B30 aren't going to be easy to find.

When does it tap? Cold vs. warm. Idling vs. revved up. Speeding up vs. slowing down.

The cam gears/thrust plates can make a nasty racket on OHV engines, but that's an easy fix.
 
Is the tapping coming from the head or the block?

What's your location? I have running B30 engine from a '69 or '70 with unknown mileage but I'd recommend trying to repair your engine if the mileage is really that low.
 
ohh interesting! Thanks for the tips, and yea, I'm wondering if I got in a little over my head for my first volvo. It was just so pretty!

The tapping happens when cold and is very hard to detect when warm. When it's idling and up through a certain RPM range I can hear it but once in the higher revs it goes away and then comes back when the RPM's drop
 
hiperfauto said:
Is the tapping coming from the head or the block?

What's your location? I have running B30 engine from a '69 or '70 with unknown mileage but I'd recommend trying to repair your engine if the mileage is really that low.
Click to expand...

Just curious if you could PM me what you'd ask for it and if you'd be willing to have it shipped ( I could arrange ). I just kind of want to have a few worst case scenarios figured out.
 
The one time my B20 had an actual bad problem (spun rod bearing) it was actually pretty quite most of the time. But got the loudest when revved up- as you closed the throttle (on the 'overrun') - it would really rattle. Oh, and the one time the 16V B230 broke a wristpin it acted similar. (How did that not blow up???)

I had a cam gear come apart once - the B20 fiber gear. B30's often have steel gears, but I'm not sure about early on. And sitting for a long time, then a bit of use, and the fiber gear coming apart is a sort of pattern of behavior you see. But that made a *nasty* tapping noise, worst at idle, less so when revved up. I think at slow speeds the torque on the camshaft goes back and forth (as the lobes pass TDC the valve can push the cam forward) - but as the revs go up it gets into a more constant pull doe to oil pump drag?

I don't think piston slap is much of a thing on an old OHV motor, but that would be worst when cold, then going away as it warms up and the pistons expand a bit.
 
Use a stethoscope to listen to the engine to get an idea where the noise is coming from. If you have really thin oil in the engine it could have some piston slap in this cold weather.
 
dl242gt said:
Use a stethoscope to listen to the engine to get an idea where the noise is coming from. If you have really thin oil in the engine it could have some piston slap in this cold weather.
Click to expand...

Or use a long screwdriver as a listening stick. Those engines have mechanical valve train that requires periodic adjustment. Find a u-tube video for a little education.
 
Few problems in life are easier to isolate and diagnose then loud tapping from a B18/20/30.
RUN from any shop that’s puzzled by ANY prominent noises from these motors.

Replace a tapping 64K mile motor without knowing what’s up?
Silly.
 
:lol: When the cam gear disintegrated on my PV's B18, the motor was still running (somehow) and making a HORRIBLE noise. Like a semi truck diesel idling. I didn't know anything better, I thought it was something serious, I took it by a Volvo specialist here in StL and they diagnosed it by sound after about 2 seconds. "Cam gear". They were backed up and couldn't fix it, so I did. Took the timing cover off and the cam gear fell right on out. Not sure how it was still spinning the cam.
 
Years ago at various times I musta’ bought a half-dozen B18/20-engined cars that sounded like they were coming apart ‘cause their fiber cam gear was in various stages of disintegration...
All’s owners had been told they needed major engine rebuild/replace.
All bulls**t.
About 2 seconds is about right...

As 164s had metal cam gear from the beginning, fracture—>separation unlikely...
At a bare minimum I think you need to adjust your valves, all 12 of ‘em.

With experience, a slotted and Phillips screwdriver, a feeler gauge and a 1/2” wrench this BASIC SERVICE can be done while waiting for a long traffic light to change.

B18/20s can be done at a shorter light.
 
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I guess you can't to the 'rule of opposites' on a B30, that sure lets you rotate a B20 around a lot less while adjusting valves.
 
Based exactly like the factory instructions for the B18/20:

—#1 piston @ TDC (compression stroke), do #’s 1,2,3,6,7,10...
—Rotate crank 360? (#6 @ TDC) and do #’s 4,5,8,9,11,12 ”

Yields gaps exactly equal to the more laborious methods...
Crank a bit harder to rotate by hand than 4 cyl tho.
 
northNH said:
As 164s had metal cam gear from the beginning, fracture?>separation unlikely...
At a bare minimum I think you need to adjust your valves, all 12 of ?em.

With experience, a slotted and Phillips screwdriver, a feeler gauge and a 1/2? wrench this BASIC SERVICE can be done while waiting for a long traffic light to change.
Click to expand...

I'm fairly certain 164s did not always come with steel gears, since I had to replace a fiber one on a '71 164 decades ago that was definitely original to the car. I do agree that this almost certainly is not causing the sound OP is hearing. Should definitely do the valve adjustment, but even after doing so, the B30 will still produce a good enough amount of tapping sound to make the inexperienced think there might be something wrong. That's just how they sound. Thicker oil, as someone mentioned, is probably a good idea.

You should also get some cam-shield and add it to your oil as soon as possible. These motors were designed to use leaded gas. Without that lead, the camshaft will get worn down even quicker than it's already definitely going to be. Cam-shield will help slow down that unfortunate process.

As long as the engine seems to be running well, do not overly worry about the tapping sound. Another thing that's definitely worth doing is a compression test. If that doesn't indicate any problems, it's another sign that your B30 is fine.
 
Leaded gas is the valve seat (99% the exhaust) recession issue.

Zinc (ZDDP) in the oil is the cam lobe/lifter issue.
 
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Wow! The person who told me this was a wonderful / knowledgeable community wasn't kidding. Thank you all so so much for these replies. I'm going to get the right oil in there and adjust the valves. I'll get a video as soon as I can. It's down a few towns away at the shop. Thinking of having it towed back this weekend.
 
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