Not so good first drive of the year. UPDATE 9/12/14 VIDEO

[Razor]

Thrust. Happens at part throttle when a slight load gets put on the motor. Pull the belt off and see how much play you have forward and back. Should be practically zero.

 

[BARRACUDA1968]

I pulled the belt and I couldn't get the balancer to move. I didn't pry real hard but it seemed tight. I talked to my engine builder this morning and he brought up a good point. He built a high end GN motor for a guy and shortly after installing the motor he took out the crank. When my engine builder took the motor apart he told the guy that something is shoving the crank forward and have his converter checked. He figured the converter was ballooning and pushing on the crank. Second time around the same thing happened again. The customer told the engine builder the converter was fine, well in the end it was the converter!

Not that this is what happened to me but I had a converter failure last year. I replaced it and away I go. The noise my motor is making now I have heard before. It was on the return road after making a pass the first time out with the old converter. It went away by the time I got to the pits. I'm new to these cars so I figured it was exhaust or something under the dash??? It concerned me the first time I heard it but since it went away I didn't think much about it when I made more passes. I drove the car a lot after going to the strip etc etc and until Saturday never had that sound occur on the street. My old converter was a restalled stock converter, nothing special like I have no so maybe I got the ball rolling with the old converter and it's taken this long to show itself.

 

[Razor]

I pulled the belt and I couldn't get the balancer to move. I didn't pry real hard but it seemed tight. I talked to my engine builder this morning and he brought up a good point. He built a high end GN motor for a guy and shortly after installing the motor he took out the crank. When my engine builder took the motor apart he told the guy that something is shoving the crank forward and have his converter checked. He figured the converter was ballooning and pushing on the crank. Second time around the same thing happened again. The customer told the engine builder the converter was fine, well in the end it was the converter!

Not that this is what happened to me but I had a converter failure last year. I replaced it and away I go. The noise my motor is making now I have heard before. It was on the return road after making a pass the first time out with the old converter. It went away by the time I got to the pits. I'm new to these cars so I figured it was exhaust or something under the dash??? It concerned me the first time I heard it but since it went away I didn't think much about it when I made more passes. I drove the car a lot after going to the strip etc etc and until Saturday never had that sound occur on the street. My old converter was a restalled stock converter, nothing special like I have no so maybe I got the ball rolling with the old converter and it's taken this long to show itself.

Disconnect the TQ converter and see how far it goes into the trans.. and be a good time to check that thrust.

 

[TurboTdr3.8]

Maybe be something like this on the converter since you already had one before ,

 

[BARRACUDA1968]

I had the converter unbolted Sunday and without really pushing on it I could only get it back just off the flywheel. I was able to start the motor and determine that wasn't the problem so I buttoned it back up. I have a lift so I could easily do it again if you tell me what thrust I am checking and how?

 

[BARRACUDA1968]

I got the motor out last night and pulled the pan. This is what I found.




Piston walls are scratched and the cam has seen better days. Looks like the lifters were riding on the outside of the lobe?




Talked to my machinist this morning at his shop and described the situation. He hasn't seen the motor yet but more than likely it will need bored so I'll have to buy new pistons. I already have forged pistons so that bites. My concern is the lifter bores, if they are damaged then the block is probably junk. Will know more when I get a chance to tear it down.

Not sure what caused this? No movement on the crank but the cam looks suspicious to me.

What do you guys think?

 

[we4Mateo]

You can busch the lifter bores if needed. I'm not sure what that material is on the pickup; almost looks like gasket, but I'm sure it's harder than that. The red stuff looks really weird to me. I'm curious what other more experienced people have to say about the cam.

 

[we4Mateo]

Do you run a tensioner on your timing chain?

 

[BARRACUDA1968]

I did not build this motor it came with the car. It's supposed to have around 4000 to 5000 miles. The material on the pickup is not magnetic and I just left everything as is until my machinist comes over today and takes a look.

Those chunks are like square slivers, almost reminds me of the chocolate sized flakes you get on deserts at fancy restaurants.

 

[Lil Truck]

Did you measure the distance between the converter and flexplate? Should be 0.100 - 0.150 to protect the crank thrust from damage.

 

[BARRACUDA1968]

Did you measure the distance between the converter and flexplate? Should be 0.100 - 0.150 to protect the crank thrust from damage.

No I didn't, never heard of that before. This is my first TR and I had a converter failure last summer so I replaced it and no one mentioned that.

 

[Lil Truck]

If a torque converter ballons due to excess load and heat it will push forward towards the crank, if there is not enough clearance it will force the crank thrust against the bearing thrust surface and grind it off. I have been told you can get away with 0.070 min. clearance with a good quality converter, I just had my converter machined for my new motor to 0.100 because the SFI flex plate and the forged crank took up clearance over the stock motor setup. Most people say 1/8-3/16 inch clearance is prefered.

 

[BARRACUDA1968]

I have at least 1/8 clearance when converter is slid back off the flywheel if that's what you mean.

 

[Lil Truck]

Yes that is good !

 

[BARRACUDA1968]

My machinist stopped over and it looks like the chain tensioner came apart. You can barely see it through the bottom of the timing cover. There's just an arm left and the spring. He figured after machining the block etc they took up the slack in the stock chain with a tensioner instead of ordering the correct size chain. Make sense.

I'll take it apart this weekend and see what the damage is.

 

[Lil Truck]

The stock chain would have been fine with the tensioner, they most likely used the wrong type of chain with the tensioner.

 

[standupjskiguy]

You mentioned the lifters, they run off center to the cam lobe
on a flat tappet setup so as to spin the lifter so the bottom wears evenly.
From what I see of the cam, it doesn't look bad to me.
The scratches that I see don't look all that deep either.
It looks like it not as bad as toy thought. Good luck.

 

[we4Mateo]

As mentioned above, they probably put a double roller on it and you can't use a tensioner with a double roller chain. And yes the FT cams do run off center to promote spinning of the lifter. I have no idea if what you have looks good or not but a FT cam does not run centered on the lifter for certain.

 

[BARRACUDA1968]

Thanks for the info and yes I do have a double roller chain so that explains the tensioner.

Tonight I took the intake and heads off. I noticed my intake is ported and it turns out it's a champion intake. I also have the CNC champion heads. The heads look fine but I will have them gone through while I'm at it. The lifter bores look fine and the cylinder walls look much better up top.

I thought I had forged pistons but they are .020 cast.

Here is a tentative plan after talking with Dave Husek. Nothing in stone but I think I might go with a 4.1 stroker hydraulic roller set up. Haven't decided on the cam yet but the goal is to go high 10's without pushing the car to the edge. I drive street mostly and like to go to the track for fun. Probably upgrade my turbo too.

I could probably salvage most of what I have depending on what I find when I get the rest of the motor apart but I plan to keep the car and I figure do it once and do it right.

 

[we4Mateo]

Good stuff.