SCOOBY DOO
BASED CANADIAN PATRIOT!!
- Joined
- Feb 18, 2007
Sounds like one or more rods knocking.
Big letdown.....
- Thread starter Superrmario
- Start date
Superrmario
Member
- Joined
- Nov 6, 2013
Found that it is a Rod.
Motor is coming out next week at the builders and going to get a full look. Once it is torn apart we can find what else if anything is wrong. I already told him I want the crank sent out for which he agreed. I hope its good. The block is going through all the basics.
If the crank is good, I am going to have it turned and re-use the old rods and replace the pistons and rings. Obviously I am going to replaced all the bearings as well.
I wanted to go with a full forged bottom end, but the additional expense is well over my budget.
You can buy a new set of NOS GM rods for $149.00.I would not use those rods if they have had the problems you and the previous owner have had for the cost of a new set.Just my opinion!
Superrmario
Member
- Joined
- Nov 6, 2013
Superrmario
Member
- Joined
- Nov 6, 2013
dartguy340
T-Type guy
- Joined
- Oct 2, 2010
The rods are cheap enough, I'd go with all new ones. 
Superrmario
Member
- Joined
- Nov 6, 2013
The rods are cheap enough, I'd go with all new ones.
Absolutely.
I'm going with a different guess. You say there is a miss when cold. I'm thinking a compromised head gasket between cylinders. I think there is a preignition jumping from the cylinder that is earlier in the firing order to the one next to it firing early so yes it is "knocking" as that is firing too soon in the rotation. I had this on a Buick 400 on the classic 5/7 fail. Same sound. Seal worse when cold so a miss. Knock less at steady RPM, worse under opening throtle.
You don't need to even get under the car--- do a compression test on all cylinders and that will tell you if 2 have become siamesed.
You don't need to even get under the car--- do a compression test on all cylinders and that will tell you if 2 have become siamesed.
Superrmario
Member
- Joined
- Nov 6, 2013
I was going to do a compression test tomorrow. We got a ton load of snow today.
Question. Did it sound like mechanical knock?
Sent from my SCH-I545 using Tapatalk
A leak down test would be much more accurate. You have to blow the shit out of head gasket to get a definitive reading from a compression gauge.
Or just use your compression gauge hose, remove the rocker shafts, and fill the middle cyls with compressed air. If you have air escape from an adjacent plug hole, you blew between cylinders.
Or just use your compression gauge hose, remove the rocker shafts, and fill the middle cyls with compressed air. If you have air escape from an adjacent plug hole, you blew between cylinders.
HighMileage
Albany,NY
- Joined
- Jul 24, 2010
Did anyone mention wrist pin? Maybe the rod is good and piston is working on the pin. ??
I'd get new rods anyway.
I'd get new rods anyway.
Thanks pacecarta for sending the link.I don't think he can go wrong with these new rods and a great deal also!
Superrmario
Member
- Joined
- Nov 6, 2013
Thx everyone for the reply and advice. I really appreciate it.
Per the issues I have been having and the "unknown" I am not got to dig any further. I say this because I am the 8th owner of the car.
Im not sure where the engine has been, how much nonsense it has been through, how much boost it has seen or how many passes.
At this point, I am going to pull the thing and have it gone over. I needed to know what is in it.
All I know is it was rebuild per two owners ago and there was quality work done 200 miles ago which I have documented.
It's just better that I have the thing looked over, build as per what my goals are and be done with it.
Mid 11 second traps at the track a few times a year and show and go for street.
Sent from my SCH-I545 using Tapatalk
Per the issues I have been having and the "unknown" I am not got to dig any further. I say this because I am the 8th owner of the car.
Im not sure where the engine has been, how much nonsense it has been through, how much boost it has seen or how many passes.
At this point, I am going to pull the thing and have it gone over. I needed to know what is in it.
All I know is it was rebuild per two owners ago and there was quality work done 200 miles ago which I have documented.
It's just better that I have the thing looked over, build as per what my goals are and be done with it.
Mid 11 second traps at the track a few times a year and show and go for street.
Sent from my SCH-I545 using Tapatalk
Last edited:
- Joined
- Feb 18, 2006
Eww, not good. Rod knock or possible cracked crank.
Pull the belt then throw a breaker bar on the balancer bolt. Go slightly back and fourth. Watch the flywheel. If the front of the crank is moving and the backs not, your crank is cracked.
Pull the belt then throw a breaker bar on the balancer bolt. Go slightly back and fourth. Watch the flywheel. If the front of the crank is moving and the backs not, your crank is cracked.
Man, I feel you for you... when I first got started in these cars >15 years ago, I went through a motor because a timing chain broke. Then, after a reasonably cheap refresh, I put it together and smashed a cheap rod bearing (didn't know at the time) by detonation. I'm sure many of us old-timers have a similar story.
I agree whole heartedly agree with Earl. I don't think these cars are actually very finicky at all, they just need to be "known" and done right the first time. AND driving the car enough to understand if it's running good or not. It's about learning your car as YOU work on it. In this case, when you bought the car, you had to trust the condition it was in. Have a beer, take your time, and you'll be happy.
I agree whole heartedly agree with Earl. I don't think these cars are actually very finicky at all, they just need to be "known" and done right the first time. AND driving the car enough to understand if it's running good or not. It's about learning your car as YOU work on it. In this case, when you bought the car, you had to trust the condition it was in. Have a beer, take your time, and you'll be happy.
No you didn't. Until you get a rod in your lap, do a visual, check it with a set of mics, a bore gauge, and check for twist you don't know nothin'.
"200 miles ago" is your big clue. With these cars I will drive hell out of an engine with 150,000 miles and not think twice... 50, 200, 500, 1000 miles and it's a core as far as I'm concerned.
I agree with Eticket. 1) Earl sounds like he knows what he's talking about... and 2) beer. duh
Superrmario
Member
- Joined
- Nov 6, 2013
No you didn't. Until you get a rod in your lap, do a visual, check it with a set of mics, a bore gauge, and check for twist you don't know nothin'.
"200 miles ago" is your big clue. With these cars I will drive hell out of an engine with 150,000 miles and not think twice... 50, 200, 500, 1000 miles and it's a core as far as I'm concerned.
I agree with Eticket. 1) Earl sounds like he knows what he's talking about... and 2) beer. duh
When I said rod, I meant rod bearing. All clues point to it, but like you said nothing is definitive until it is torn down. It will be very soon.
200 miles ago the car was repaired by a very reputable guy. I have receipts and odometer readings to show.
Well see what happens. Again, at this point it doesn't really matter. I want the whole thing torn down to a bare block and inspected. I want to know what is in it, and what it's condition is.
Sent from my SCH-I545 using Tapatalk
You'll see when messing with these cars they fail in two different ways... either right off the bat the engine fails from a fresh build.... OR they get broken from a tuning mistake and the engine gets blamed for high mileage....
OR they go for hundreds of thousands of miles and stay together with 'pure luck'.
OR they go for hundreds of thousands of miles and stay together with 'pure luck'.
Superrmario
Member
- Joined
- Nov 6, 2013
I wish I was down the "pure luck" Avenue right now which I know is sarcastic for "taken care of and tuned right"
Sent from my SCH-I545 using Tapatalk
Similar threads
