Engine rattle

7173Mustangs.com

Help Support 7173Mustangs.com:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
D

don29163

Well-known member
7173 Mustang Supporter Member
Joined
Feb 23, 2011
Messages
514
Reaction score
2
Location
Santee, SC
My Car
72 Mach I Q code
61 Impala
67 Chevelle
78 Bradley GT II
I have a rattle in my 351C, I almost know what it is but just need to hear it from someone, I reckon. Runs great, oil light goes right off and doesn't blink at idle, but about the time you shift gears...no high rpm's.. it starts rattling.. like it has marbles in there somewhere. I pulled the pan before it went in and the bearings looked good. I know, I should have gauged them...but I didn't. Could it be carbon on top of a piston? other thoughts ? Not a deep knock like a main, just a rattle.

 
Last edited by a moderator:
I have a rattle in my 351C, I almost know what it is but just need to hear it from someone, I reckon. Runs great, oil light goes right off and doesn't blink at idle, but about the time you shift gears...no high rpm's.. it starts rattling.. like it has marbles in there somewhere. I pulled the pan before it went in and the bearings looked good. I know, I should have gauged them...but I didn't. Could it be carbon on top of a piston? other thoughts ? Not a deep knock like a main, just a rattle.
Click to expand...
Does it rattle idling or if you rev up in park?? could be several things depending on when it happens, if it mainly happens after deceleration i would say mains or rods and a possible stretched timing chain. Just a couple of guesses

 
Last edited by a moderator:
does it on acceleration. It is a 4 speed but about the time you shift gears...
Click to expand...
Possible throw out bearing?? also on acceleration it could be pre ignition.
Click to expand...
X2 on detonation. Mine did the same thing and I found the cam advanced 11* when we degreed the cam. My rod bearings were hurt on the rod side, no damage on the cap side. Pulling caps do not give the whole story.

 
Try taking a few degrees of advance out to see if it changes. Last tank of gas from a different station??? Just taking shots in the dark. Chuck

 
Sounds like pre ignition to me.

If you have gotten gas from a different station and it was not exhibiting the problem previously, I would say it is definitely pre ignition.

BT

 
Without hearing it, I would agree with the others that it it is likely pre-detonation. However, the 351C in the 72 Mach 1 I used to have had sat for a long time before I bought it and rattled on acceleration and even at idle after running for a while. I always figured it was the hydraulic lifters as I could put in 20w50 oil at oil changes and the rattle would stop or at least minimize.

 
88 k , I pulled the pan, looked at a couple of rod and main bearings, they looked fine..I put a new timing set in just for good measure and replaced the front and rear seal. I know...hindsite.

Maybe this post will make someone else more careful. Wasn't the only goof I did on this build. I guess the worst pill to swallow is that I know better.

 

Similar threads

Doc302
Oil pressure
Replies
13
Views
624
Bill Kanode
B
Austin Vert
AUSTIN VERT'S LOVE/ HATE THING WITH RATTLE PAINT CANS
Replies
0
Views
605
Austin Vert
Austin Vert
California 72
Lower Engine Seals and Gaskets
Replies
6
Views
447
rcadd1ct
R
andy72
351C IDLE SPEED PROBLEM, FMX CLUNK?
2
Replies
32
Views
3K
AcesArneson
AcesArneson
P
351C 2V Heads Help
2
Replies
27
Views
2K
will e
W

Latest posts

Back
Top