What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

Sewing machine sound at idle on K5

wazzabie

wazzabie

1/2 ton status
 Premium
Joined
Apr 17, 2001
Posts
2,922
Reaction score
447
Location
Washington State
At idle the K5 with a 350 sounds like a sewing machine. After I give it some gas the sound goes away. Going down the road at speed I don't hear the sound. Could this be related to engine timing? There has been no change made to valve lash. I did adjust the carb.
 
You may have some rocker/lifter noise. Once the oil pressure increases and/or the engine speed increases it fades

Have a stethoscope?
 
Bent77 said:
You may have some rocker/lifter noise. Once the oil pressure increases and/or the engine speed increases it fades

Have a stethoscope?
Click to expand...
Yes I have a stethoscope.

The oil pressure never gets to zero. The oil pressure gauge does swing about at times.
 
wazzabie said:
Yes I have a stethoscope.

The oil pressure never gets to zero. The oil pressure gauge does swing about at times.
Click to expand...
It doesn’t have to get to zero, and we’re really hoping it doesn’t!

Sometimes when the lifters start to get soft, they won’t pump up at low pressure, so it will be more noticeable when hot

Once the RPM increases, pressure goes up and they recover, taking the lash out

What weight/brand/type of oil are you using?
 
Time for some 20W-50 oil or SAE30 wt oil....Marvel Mystery oil will quiet + flush out grungy engine oil
 
Bent77 said:
It doesn’t have to get to zero, and we’re really hoping it doesn’t!

Sometimes when the lifters start to get soft, they won’t pump up at low pressure, so it will be more noticeable when hot

Once the RPM increases, pressure goes up and they recover, taking the lash out

What weight/brand/type of oil are you using?
Click to expand...
Valvoline 10w-30. The motor oil was recently changed using old stock motor oil from 1996. The good stuff back when it still had some zinc.
 
Last edited:
wazzabie said:
Valvoline 10w-30. The motor oil was recently changed using old stock motor oil from 1996. The good stuff back when it still had some zinc.
Click to expand...

That's like the worst thing you can do. Oil absolutely goes bad sitting in the jugs, just saw a test on this very topic. Additives separate out and don't remix. Toss it and replace it with new.
 
dyeager535 said:
That's like the worst thing you can do. Oil absolutely goes bad sitting in the jugs, just saw a test on this very topic. Additives separate out and don't remix. Toss it and replace it with new.
Click to expand...
What brand of motor oil and viscosity do you recommend?
 
Also make sure you have a good filter. I was in a rush once and ended up with an orange filter and the engine made weird noises. Probably over the years it had some other form of Fram at some point, but in that case doing nothing but getting an AC Delco filter fixed the problem.
 
Blue85 said:
Also make sure you have a good filter. I was in a rush once and ended up with an orange filter and the engine made weird noises. Probably over the years it had some other form of Fram at some point, but in that case doing nothing but getting an AC Delco filter fixed the problem.
Click to expand...
I'm using a WIX filter. I have some old stock early 1990s AC Delco filters.
 
I mean no one really knows what a good oil is unless they test it. Any testing I've seen online of late says all oils sold (of those tested) are good quality. I last bought five quart jugs from Costco (store branded) as it was cheap and came with two jugs each of two separate viscosities, which works since I have two vehicles that take the two different viscosities.

Flat tappet anymore, I'm not sure. I'd rely on those interested in keeping their flat tappets happy, as there has been much discussion specific to that. I'm roller, so I run what's cheapest.

I've gotten good deals on Wix, Bosch, and Mobil 1 filters. I would be surprised if new filters are not better than older ones. Tolerances are far less, synthetic filter media is much more common, and technology in general has advanced a lot. Not sure I'd run filters that old. That said, I've got Mobil 1 filters I got from Kmart when they closed down, but those were high end back then and I believe synthetic too.
 
Last edited:
If you can find vr1 in 10w40 get that. Most common is vr1 20w50. Lucas, Brad Penn have high zinc 10w40. Probably have to order those, I do.
 
Update: The sewing machine sound does not happen when the engine is in park or neutral. I have the spedo cable disconnected at the tcase. I wonder if the noise could be from the spedo cable. A long time ago I did the th350-np203 to th350-np205 swap. The cable was too long and required some odd bends so I left it unattached.
 
Can be, I had one that made a bit of a chirping sound, but only sometimes
 
I changed the motor oil out using Lucas Classic 10w-40 motor oil. I also disconnected the spedo gauge and tied it out of the way. I still get the sewing machine sound at idle. I'm finding that the noise is intermediate. On one occasion there was no noise when I had the engine in park and neutral. The moment I put the vehicle in drive there was the noise. At startup in park there is the noise. Thoughts?
 
wazzabie said:
What would cause a cracked flex plate? How would that be diagnosed.

I'm thinking perhaps a noise alternator? I'm not sure.
Click to expand...
They just crack sometimes…metal fatigue.
Definitely pull your belt/ belts off then run it and see if the noise goes away. Just keep an eye on your coolant temp.
On the flex plate, you have to pull the inspection cover and remove the torque converter bolts. Push the converter back away from the flex plate and start it up.
 
Yep pull the belts to narrow it down. I had a power steering pump make a knocking sound one time, sounded like bearings. Took the belt off, noise gone.
 
You must log in or register to reply here.

Latest Posts

Top Bottom