70 something 250 makes noise

[Anonymous]

I have a 1970 something Ford 250 ci engine in a 1967 Falcon van. It just started making noise like a diesel engine (not valve ping, although it does that too) only in the middle range of throttle and worse if over 60 mph. If you are accelerating or decelerating it doesn't do it. It does it worst when you are maintaining a constant speed over 60. Could this be the main bearings and what do you recommend to fix it?

 

[FAR OUT]

maybe torque converter bolts loose.

 

[Anonymous]

Leroy- go to 240-300 forum, see pushrod noise, ...Larry

 

[rbohm]

8) one of my college instructors mentioned that sometimes on ford sixes when the trans fluid is low the torque converter knocks and it sounds like a main bearing knock. check the trans fluid first, assuming you have an automatic.

 

[Anonymous]

I do have an automatic C4 and I just pulled it to replace the front pump seal and bearing less than 500 miles ago. I will check the torque converter bolts and fluid level, but I checked the fluid before my 140 mile trip and it was full. It doesn't really do it much at all under 60 mph or when I'm not towing. I just changed the oil and added 10w-40 before the trip (towing 900 lbs). It did not use or leak any oil. I first noticed the noise in between shifts when under a load. it rattled as the engine rpms dropped from one gear to the next, during the float time in-between gears. as long as you're giving it gas or coasting there was no noise. I keep reading where the 200-250 are nearly bulletproof, does that mean it's unusual for the mains to go bad in them?

 

[Anonymous]

I checked the torque converter bolts, and all the u-joints, they were tight. I checked the tranny fluid level, it and the motor oil are full. The strange thing is now it won't make the noise, I suppose it had something to do with towing a trailer. If I had a rod bearing knocking, I would guess it would do it all the time and get worse with time. Can a main bearing make noise and then not make noise?

 

[Anonymous]

I found a major vaccum leak today, the line running to the modulator on the transmission had a hole burnt in it from the exhaust. After replacing it I was able to set the timing back quite a bit, I had advanced the timing to get it to run, the engine is real quiet now and I don't hear that noise in between gears.

 

[Anonymous]

glad you got it fixed

 

[Anonymous]

it's not fixed yet, heard it again last night. My buddy said it sounds like lifter noise, maybe pushrod noise like the other thread was talking about. I am going to adjust the rocker arm bolts tonight and see if it goes away.

 

[Anonymous]

good luck don`t ya just hate it when things come back and bite ya in the but :x

 

[Anonymous]

there are no adjustment bolts on my rocker arms, there are only bolts on the cam assembly that hold it all down. I noticed several worn pushrods http://allaboutmud.com/images/pushrods.jpg I am going to replace. Once again I am in trouble because I don't know what year 250 I have. Do you think there are different length push rods for different 250 engines or are they all the same? and would that cause chattering in the valve train?

 

[Anonymous]

just tell the parts store that you need the liftors and pushrods for a 75 maverick or granda with a 250 (if the pushrods are worn the liftors probly worn too ) this should solve the problem tighten the bolts to 30 - 35 ft lbs if you don`t have torque wrench get one there only 10 bucks

 

[Anonymous]

the noise is gone. three bad pushrods were the culprit.

 

[61Futura]

I've got that kind of a rattle noise with my "63 170 with '60 2spd auto. It takes about 1 minute after a cold start before it happens. Then at idle it rattles. It runs pretty quiet when driving it. Using a heater hose as a stethiscope, I thought I tracked it to the torque converter. All of the head bolts transfer a lower volume level of this noise also. The rocker arms were all quiet. I pulled the tranny & put my spare torque converter on but still have the noise. I just put the drive train together from used parts. I hope it isn't a bearing problem. I thought the torque converter was going to fix it because it looked like it was rubbing against the trannys front pump. Maybe both converters will hit the pump. I did swap the input shaft from a '61 2spd auto from a 170, into a '60 2spd auto from a 144. The engine was supposed to be a fairly new rebuild, & had honing marks on the cylinder walls the first time I bolted on a head. Those marks were gone when I pulled the head after 200 miles or so, because I had 2 leaking exhaust valves. It has a rebuilt head with adjustable & adjusted rockers. I'm stumped. I wish it could be push rods for me.

Steve