Tick/clatter at idle

[1970cat]

have you tried to take a long screwdriver or piece of hose and put it to your ear? with the engine running it will act like a stethoscope to help narrow down the source of the sound.

 

[Jon O.]

I had forgotten about that trick. Jammed something against the brake pedal, put the emergency brake on, and put it in gear. And then I did some snooping with a long rubber hose. Front of transmission where the torque converter is, some whirring, but no clatter. Brake booster, no sound. Top of valve cover on driver's side had the ticking. Top of valve cover on passenger side had the ticking but slightly louder. Both exhaust manifolds were too loud with other noise to hear the ticking. Alternator, nothing. A/c clutch, some whirring but no ticking.
So I think that it may be a valve or two.
The real question is: Why does pushing the brake pedal have anything to do with valves?

 

[Big_John]

I had forgotten about that trick. Jammed something against the brake pedal, put the emergency brake on, and put it in gear. And then I did some snooping with a long rubber hose. Front of transmission where the torque converter is, some whirring, but no clatter. Brake booster, no sound. Top of valve cover on driver's side had the ticking. Top of valve cover on passenger side had the ticking but slightly louder. Both exhaust manifolds were too loud with other noise to hear the ticking. Alternator, nothing. A/c clutch, some whirring but no ticking.
So I think that it may be a valve or two.
The real question is: Why does pushing the brake pedal have anything to do with valves?

The RPM may be dropping just enough when it's in gear with brakes on that the oil pressure drops. Oil pressure drops and the lifters will rattle.

 

[Jon O.]

The RPM may be dropping just enough when it's in gear with brakes on that the oil pressure drops. Oil pressure drops and the lifters will rattle.

Thank you, maybe the oil pump needs a rebuild then. It has a slow oil leak in that area.

 

[Big_John]

Thank you, maybe the oil pump needs a rebuild then. It has a slow oil leak in that area.

You really need to check the oil pressure before you start doing things like replacing the oil pump.

My speculation is kind of a shot in the dark without actually hearing the noise. You've done well by isolating the noise to the valve cover and given that and your description, it's probably a lifter noise. It could be oil pressure, but it could also be a bad lifter. A bit of good old fashioned diagnostics is in order.

 

[1970cat]

any recent backfires or run on after shut down?

 

[Jon O.]

any recent backfires or run on after shut down?

No backfires or run on at any time ever. Only odd thing i can think of is the last time i used it for errand running, i was backing out of a parking space and it almost died like it was starved for gas, then surged for a half second before going back to normal.

 

[1970cat]

ok, just thinking out loud on the backfire. there are several things that can cause bent push rods. bled down or collapsed lifters, severe backfire, stuck valves etc. just another possibility.

 

[LeBaron1973]

Perhaps you had a temporary fuel starvation issue, then too much when the blockage cleared before returning to normal, else there's some @!$% in the tank which blocks the fuel pump, and clears again.

I wish you happy motoring again once this issue is resolved.

 

[Jon O.]

ok, just thinking out loud on the backfire. there are several things that can cause bent push rods. bled down or collapsed lifters, severe backfire, stuck valves etc. just another possibility.

Bent pushrods? I think (hope) this is way simpler than that. I forgot to mention the car has its original timing gear, and i have no idea when the timing was last done or if any of that could factor into this. Like i said, this car gets very little miles put on, and is driven extremely gently. The sound just started not long ago, and is barely audible (im also hard of hearing.) Just trying to address before it turns into something bigger.

 

[MoPar Maniac]

PCV valve? (If on L side)

 

[Jon O.]

I'm going to wait until this weekend and check oil pressure and go from there. For now she sits and waits!

 

[Jon O.]

As per my grandpa's advice, I bought the best Fram oil filter I could find. He said since I had a cheap filter on there, that it could be part of my problem.
What weight oil would you use in temperatures below freezing?
What weight oil would you use in temperatures from 50-above 100 degrees (Fahrenheit)?
I use Castrol GTX, and is hard to find anything other than 10w30. Grandpa says that that 10w30 may be too thin for use in the summertime.

 

[Ripinator]

As per my grandpa's advice, I bought the best Fram oil filter I could find. He said since I had a cheap filter on there, that it could be part of my problem.
What weight oil would you use in temperatures below freezing?
What weight oil would you use in temperatures from 50-above 100 degrees (Fahrenheit)?
I use Castrol GTX, and is hard to find anything other than 10w30. Grandpa says that that 10w30 may be too thin for use in the summertime.

I mean no disrespect to your grandfather, but you need to ditch that Fram filter ASAP. Fram filters are notorious for having inferior filtering materials and malfunctioning relief valves. Go down to NAPA and buy a NAPA Gold filter (actually made by WIX). Also, you can go to Summit.com and order six quarts of high zinc content Brad Penn / Penn Grade 15W-40 or 20W-50 oil (they also sell WIX filters). You should not use today's conventional oils in your flat tappet cam engine. Without the high zinc / phosphor additive package, you are at high risk of wiping your cam.

 

[Jon O.]

I mean no disrespect to your grandfather, but you need to ditch that Fram filter ASAP. Fram filters are notorious for having inferior filtering materials and malfunctioning relief valves. Go down to NAPA and buy a NAPA Gold filter (actually made by WIX). Also, you can go to Summit.com and order six quarts of high zinc content Brad Penn / Penn Grade 15W-40 or 20W-50 oil (they also sell WIX filters). You should not use today's conventional oils in your flat tappet cam engine. Without the high zinc / phosphor additive package, you are at high risk of wiping your cam.

How long have you been using brad penn oil? I always heard that they were no good. My highschool science teacher told me about castrol gtx. He mixed it with stp zinc additive. And he had a car from the 70's that he bought new that has lasted almost 400,000 miles and might still be running. And he always preached his blend of castrol every 3,000 miles on the dot. So you can see why I would be reluctant to change that. I am completely unsure what weight he used.
And ill go get a napa gold filter. I have heard from many members here that they are good. Do you know if they have a better flow rate?

 

[Ripinator]

How long have you been using brad penn oil? I always heard that they were no good. My highschool science teacher told me about castrol gtx. He mixed it with stp zinc additive. And he had a car from the 70's that he bought new that has lasted almost 400,000 miles and might still be running. And he always preached his blend of castrol every 3,000 miles on the dot. So you can see why I would be reluctant to change that. I am completely unsure what weight he used.
And ill go get a napa gold filter. I have heard from many members here that they are good. Do you know if they have a better flow rate?

I've been using the Penn Grade (used to be Brad Penn, but the name got changed) 20W-50 oil in my '66 300 for the last couple of years. Before that, the cars I had used roller hydraulic cams, so there was no issue regarding cam wear. I am currently breaking in a new 440 engine in my other '66 300, and for that break-in I'm using Comp Cams' 15W-40 break-in oil (very high ZDDP content). When the break-in is done, I'm gonna switch to Penn Grade 15W-40 in that car.

As regards flow rate: I don't know, but WIX makes a high-flow race filter (also available from Summit), but I don't think our cars need it. The regular WIX premium filter is what we need. We want good filtering - not high flow.

Also, I don't think mixing STP zinc additive with conventional oil works as well as using an oil with a high ZDDP package that was added during the manufacturing process. Besides. . . I never trusted high school science teachers. . .

 

[Jon O.]

I actually think I have a vacuum leak. If I have someone press the brake pedal and I check around for noises with a hose, there is some under the valve cover, I have no idea if that is normal or not. But the brake booster check valve makes the noise when I have the hose on it. If I take some pliers and pinch off the vacuum hose, the engine stops clattering. It has been oddly idling pretty fast.
I checked the oil pressure and it is fine.

 

[Ripinator]

I actually think I have a vacuum leak. If I have someone press the brake pedal and I check around for noises with a hose, there is some under the valve cover, I have no idea if that is normal or not. But the brake booster check valve makes the noise when I have the hose on it. If I take some pliers and pinch off the vacuum hose, the engine stops clattering. It has been oddly idling pretty fast.
I checked the oil pressure and it is fine.

I think your brake booster has taken a dump. I had mine go at about the same mileage you have on your car. If its leaking vacuum, the engine would behave pretty much the way you describe.

 

[Jon O.]

I think your brake booster has taken a


I think your brake booster has taken a dump. I had mine go at about the same mileage you have on your car. If its leaking vacuum, the engine would behave pretty much the way you describe.

Thanks for your help. Its surprising that it can cause so much trouble in parts that are unrelated. Ill replace the $5 check valve and see if that does anything, if not ill get a new booster.