Front Engine Rattle on my 225..

[RobsIron]

I have a new Buick 225 V6 in my Willys Jeep. It only has a couple hundred miles on it. This weekend I removed the carb because the base was loose. Reinstalled and now it has a loud rattle noise near the front of the engine and will only run for about 10 seconds. The rattle sounds like the fan is hitting something even though its not. What do you guys think? Timing chain? Distributor? Working on the carb has to be just a coincidence..

 

[charlief1]

Pull the distributor or fuel pump so you can see the timing chain. Did you convert to HEI?

 

[RobsIron]

Has an elec fuel pump. No HEI. Timing chain is new, but I was thinking Im gonna have to pull the distributor..

 

[charlief1]

Change over to HEI and I have a feeling that the tensioner may be the issue along with the chain Rob.

 

[RobsIron]

If it is...time for a hotter RV cam!

 

[ek02]

Any chance that something fell into the intake when the carb was off and went into a cylinder ? I hope that's not the case, but I have seen it happen many times. Odd fire timing chains can make the distributor rattle when they are worn also, but yours is new. Maybe the tensioner came apart, like Charlie said.

 

[fastblackracing]

a friend of mine has a boat with a sbc with a Q-jet on it and his highly skilled brother dropped a small 1/4" flat washer from the air cleaner into the carb and left it there for whatever reason......... So they get the boat running and he comes into work one day and asks me to look at it.....says it was making a bad rattle/grinder noise and then it stopped and now it has a little knock....... when I tore down the engine I was shocked at what I found,,,,, that washer had traveled back and forth thru all 4 cylinders that were on the 1 side of the dual plane intake plenum and beat the piston tops to death until a small piece that was left of the washer parked itself onto one piston in the squish area and was banging into the head every revolution. Never would of thought it could go back and forth like that. Does the engine start right back up? What controls the fuel pump?

 

[RobsIron]

Any chance that something fell into the intake when the carb was off and went into a cylinder ? I hope that's not the case, but I have seen it happen many times. Odd fire timing chains can make the distributor rattle when they are worn also, but yours is new. Maybe the tensioner came apart, like Charlie said.

a friend of mine has a boat with a sbc with a Q-jet on it and his highly skilled brother dropped a small 1/4" flat washer from the air cleaner into the carb and left it there for whatever reason......... So they get the boat running and he comes into work one day and asks me to look at it.....says it was making a bad rattle/grinder noise and then it stopped and now it has a little knock....... when I tore down the engine I was shocked at what I found,,,,, that washer had traveled back and forth thru all 4 cylinders that were on the 1 side of the dual plane intake plenum and beat the piston tops to death until a small piece that was left of the washer parked itself onto one piston in the squish area and was banging into the head every revolution. Never would of thought it could go back and forth like that. Does the engine start right back up? What controls the fuel pump?

The first thing I was worried about was that something fell in. I pulled the plugs on the passenger side and one had shiny nicks on it. I have a small rare earth magnet with a hole in it. I tied it to a piece of wire and pushed it in with a coat hanger and retrieved a small piece of lightweight metal. Kinda looks like a piece of cotter pin. Thinking that may be the problem I reinstalled the plugs and tried to start and the noise sounded even more towards the front. I have a borescope and am going to see what the heck is happening in all cylinders before I try to start again.

 

[charlief1]

It just occurred to me, do you have a fuel pump block off on it? That might give you a good look inside if you take it off.

 

[RobsIron]

It just occurred to me, do you have a fuel pump block off on it? That might give you a good look inside if you take it off.

There is. I'll do that.

 

[ek02]

You may have found your problem. Usually, the foreign object imbeds itself in the piston and hits the head causing the noise. I have had some where I just removed the object and put it back together, and others where it did major damage. Ball bearings, nuts, carb pieces, and melted piston pieces in the old intake installed on a new engine are some of the things I have seen causing a knock. It happens.