4.3 knocking...

Nuts · 04-30-2010, 05:43 PM

ITS NOT THE ROD OR MAIN BEARINGS!!!! But there is a loud knock coming for my 4.3. The motor is a 97 or 98, is there anything thats known for hammering on these?

yellowjacket · 04-30-2010, 06:46 PM

is it knocking the same in neutral as in gear with a load?

Redriverranger · 04-30-2010, 07:58 PM

If it's an auto, maybe loose torque converter bolts, or cracked flywheel.

sarge · 04-30-2010, 08:15 PM

that is what mine is doing beed that way for over a year , I'll second Casey's diagnosis , I'm going to dig in to mine while it's under the knife and see what it is . Load doesn't change mine knock.

Nuts · 05-01-2010, 09:51 AM

Load doesn't change it, and all the convertor bolts are tight and the fly wheel is good. I know this because i just put the motor in... Its kind of a high pitched knock, and I'm starting to think the crank is hitting the windage tray in the oil pan.

Redriverranger · 05-01-2010, 05:56 PM

I had a 4.0 ford knock like hell for about 10 minutes once when I first installed it. I wouldn't have given you two cents for it and was about to yank it back out of the truck. Then I thought what the hell, what have I got to lose and revved the hell out of it. It got quieter. I pushed it a little more and it finally got very quiet and was an extremely good motor for about 4 years. I know this is probably the exception to the norm, but I feel that the engine had some power steering fluid or tranny fluid that ran down in the intake, as it was sitting at a junkyard under a shelf with other engines above it that created a hot spot, or detonation point when I started it, hence the knock. That is the only way I can explain what may have caused it as it truly ended up a great engine.

04-30-2010, 05:43 PM	#1
Nuts Join Date: Feb 2008 Location: middletown,oh Posts: 508	4.3 knocking... ITS NOT THE ROD OR MAIN BEARINGS!!!! But there is a loud knock coming for my 4.3. The motor is a 97 or 98, is there anything thats known for hammering on these?

04-30-2010, 07:58 PM	#3
Redriverranger White ranger guy Join Date: Nov 2007 Location: Red river gorge,ky Posts: 274	If it's an auto, maybe loose torque converter bolts, or cracked flywheel. __________________ 91 Ranger ext cab, 60, 14 bolt, 4:88's, 39.5's, doubler, lot's of character

05-01-2010, 05:56 PM	#6
Redriverranger White ranger guy Join Date: Nov 2007 Location: Red river gorge,ky Posts: 274	I had a 4.0 ford knock like hell for about 10 minutes once when I first installed it. I wouldn't have given you two cents for it and was about to yank it back out of the truck. Then I thought what the hell, what have I got to lose and revved the hell out of it. It got quieter. I pushed it a little more and it finally got very quiet and was an extremely good motor for about 4 years. I know this is probably the exception to the norm, but I feel that the engine had some power steering fluid or tranny fluid that ran down in the intake, as it was sitting at a junkyard under a shelf with other engines above it that created a hot spot, or detonation point when I started it, hence the knock. That is the only way I can explain what may have caused it as it truly ended up a great engine. __________________ 91 Ranger ext cab, 60, 14 bolt, 4:88's, 39.5's, doubler, lot's of character

04-30-2010, 06:46 PM	#2
yellowjacket barely breathing Join Date: Mar 2008 Location: alexandria, ky Posts: 889	is it knocking the same in neutral as in gear with a load?

04-30-2010, 08:15 PM	#4
sarge Pure Bacon Join Date: Jan 2007 Location: Trenton, Oh Posts: 1,098	that is what mine is doing beed that way for over a year , I'll second Casey's diagnosis , I'm going to dig in to mine while it's under the knife and see what it is . Load doesn't change mine knock.

05-01-2010, 09:51 AM	#5
Nuts Join Date: Feb 2008 Location: middletown,oh Posts: 508	Load doesn't change it, and all the convertor bolts are tight and the fly wheel is good. I know this because i just put the motor in... Its kind of a high pitched knock, and I'm starting to think the crank is hitting the windage tray in the oil pan.