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Stressed out with engine

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gyuen

Probationary Member
8
0
Aug 3, 2002
Calgary,
I got a 95 Talon and just finished getting a SCM-61 turbo, 780 injectors, Eagle rods, CP pistons, ARP Hardware and pretty much everything necessary. I've had no problems with crankwalk with a 16G, FMIC, and ACT 2600lb clutch. I get a call from the machine shop to find out I got a crack by the waterpump area. So now I've got all these damm parts for a 7 bolt motor. Some guys told me to JB weld it. AHH don't think so. The only other motor I found locally was a 93 4G63 NA motor. Any help guys. Thanks.
 

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the machine shop should be able to fix it, they might be able to weld it. and depending on they depth of the crack and the location, if it is not in a critical spot you might be able to epoxy it. but either way it is not the end of the world, you can probably find a motor in a junkyard or something for next to nothing, and then you have extra parts as well. hope it works out for you.
 
I have a machined 7 bolt motor that I could sell .... it would just need to be rehoned because there are 4000 miles on it since the machining. It's bored .020 over. I don't know how much shipping would be to canada though :-/
 
i would just get a 6 bolt block, it looks like you want to make alot of power, and with a 7bolt and 2600, you are just asking for crankwalk. :thumb:
 
look at almost all high powered dsms, hmmm, they have a 6 bolt block! you could get lots of power out of a 7 bolt, don't get me wrong, but i would rather spend the money and build a 6 bolt, but thats just my "terrible advice". :talon:
 
the oil squirters do keep the piston cooler, i have heard of people not using them, alot of the drag dsms don't use them, but they do not get ran as much as a street driven dsm.
 
Sell all your 7 bolt related parts and get a six bolt. A high powered 7 bolt block will eventually crankwalk. The thrust bearings just were not designed to hold up to major power. If you decide to go with a 7 bolt now, you'll be kicking yourself a few months from now when your crank goes walking.
 
sonicnofadz said:
Sell all your 7 bolt related parts and get a six bolt. A high powered 7 bolt block will eventually crankwalk. The thrust bearings just were not designed to hold up to major power. If you decide to go with a 7 bolt now, you'll be kicking yourself a few months from now when your crank goes walking.

I'm not trying to start shit, more playing devils advocate. What about the 11 sec 7 bolt powered street cars? Alot of folks here think crankwalk is overblown. I think he should stick with the 7 bolt IF he can get this block repaired because I know about financial restraints (not saying no one else does). But selling all those parts just to start over is pretty harsh.
 
Crankwalk is not overblown. There are many machine shops that will refuse to rebuild a 7 bolt block because they know it will just crankwalk again. Sure there are alot of guys that can put down decent power with a 7 bolt, but its only a matter of time before they will have to rebuild. There is a simple decision here: decide to build up a block that has known to have serious reliability issues just because it would be a pain to get rid of all the 7 bolt specific parts, or start fresh with a block that is known to be reliable. If you ask me, I consider using the 7 bolt block a huge risk. The more and more he invests into it, the more that will be wasted if it walks (which it probably will if hes gonna be putting down alot of power). Who knows maybe it will never have crankwalk, but it is these types of chances I would rather not play with. If there is one thing I have learned when working with cars, is that it is better to do things right the first time then to have to redo it all over again further down the road.
 
Mike000 said:
why? (or is that sarcasm?)
The 6 bolt motor lacks the girdle a 7 bolt motor does. Aside from that, they don't have oil squirters, which lots of people plug for higher oil pressure.

In stock form 6 bolts are best in strength. When you're building a motor, that doesn't matter. The 1g 7bolt block design is just better to work with when building a motor IMO.
 
Stapl3 said:
The 6 bolt motor lacks the girdle a 7 bolt motor does. Aside from that, they don't have oil squirters, which lots of people plug for higher oil pressure.

In stock form 6 bolts are best in strength. When you're building a motor, that doesn't matter. The 1g 7bolt block design is just better to work with when building a motor IMO.

I'm going to have to second this, although I'd like to clarify. 1G Turbo blocks have "squirters", as do 2G Turbo's, but in a vastly different design. 1G NON-Turbo blocks do not have "squirters". Many people have done very well without oil squirters. The 1G Non-Turbo 7 Bolt retains the positive additions to the late 4G63, such as the block girdle. If you can get your hands on a late '92-'94 NT 7-Bolt, by all means bolt it up. You won't have to do all the little things that a 6-bolt conversion requires, such as the water pipe, wiring, CAS sensor, etc. Plus, you can keep your existing parts that are still good.

However, do NOT attempt to do something like this on a STOCK NT block. Have it cleaned, decked, bored .020 over with forged pistons and rods, with the balance shaft eliminator kit installed. Have the rotating assembly zero balanced. If you've already built a 7-bolt, you probably know all of what I'm saying.

That would make for a killer setup, and would address the main problem with the 7-bolt 4G63: A check valve installed on the thrust bearing main oil galley. (what most people refer to as "squirter")

Personally, I think that this theory is partly right and partly wrong. Let me explain. I have a 2G which has one of the earliest build dates in existance (March of 1994). As such, it is a rare 'hybrid' with strange things like an ECI-Multi badge on the intake manifold, strange ECU code, ground straps from nowhere, and vented rear discs. I recently rebuilt the motor with all forged components. Upon disassembly, with 180,000 very hard miles on the block, we checked crank end play. The reading was .0037. With 180K on the clock. After we rebuilt the motor with the new components, the reading was .0035. Perfect. So, after 180K and no crankwalk, what makes this motor, and the 1G seven bolts, different than the later 2G seven bolts?

The metal. The later 2G motors were made from a different composite metal alloy than the 1G 7-bolts and very early 2G's. I have been told that this happened when the block casting process was switched over to Hyundai. I have yet to see this proven, but it makes perfect sense. How do I know this? When boring the block, my machinist had found that the boring machine was taking significantly longer to cut my block, as well as the 1G blocks, than the later 2G's. This is because it is made of a different material.

I believe a weaker block alloy combined with the poorly designed check valves in the main galley is the primary reason why 1G 7-bolts do not walk nearly as often as 2G's.

Makes sense, doesn't it?


Matt.
 
Yes it does make very much sense. :thumb:

one question though. Why does the thrust bearing wear and not the block if it is weaker? or when the girdle is torqued down does it misalign the rest of the motor?
i had almost 3mm of endplay when i pulled my 7 bolt

gyuen. I rebuilt my 7 bolt only to have it walk in 10,000 miles don't risk it.
I wish i was smart enough to have just done the fully built 6 bolt swap the first time and save myself 2,000 bucks. i was nervous about all the conversion stuff but its not hard at all. But live and learn.

JJ
 
It was my understanding that 2g turbo blocks do not have oil squirters. We disassembled my friends crankwalked motor, and I couldn't find the squirters to save my life.

You hit on some good points with using the 7bolt block that I didn't even touch on. CAS, waterpipe, etc. Kinda makes me hate the 6 bolt hype.
 
Enraged78 said:
I'm going to have to second this, although I'd like to clarify. 1G Turbo blocks have "squirters", as do 2G Turbo's, but in a vastly different design. 1G NON-Turbo blocks do not have "squirters". Many people have done very well without oil squirters. The 1G Non-Turbo 7 Bolt retains the positive additions to the late 4G63, such as the block girdle. If you can get your hands on a late '92-'94 NT 7-Bolt, by all means bolt it up. You won't have to do all the little things that a 6-bolt conversion requires, such as the water pipe, wiring, CAS sensor, etc. Plus, you can keep your existing parts that are still good.

However, do NOT attempt to do something like this on a STOCK NT block. Have it cleaned, decked, bored .020 over with forged pistons and rods, with the balance shaft eliminator kit installed. Have the rotating assembly zero balanced. If you've already built a 7-bolt, you probably know all of what I'm saying.

That would make for a killer setup, and would address the main problem with the 7-bolt 4G63: A check valve installed on the thrust bearing main oil galley. (what most people refer to as "squirter")

Personally, I think that this theory is partly right and partly wrong. Let me explain. I have a 2G which has one of the earliest build dates in existance (March of 1994). As such, it is a rare 'hybrid' with strange things like an ECI-Multi badge on the intake manifold, strange ECU code, ground straps from nowhere, and vented rear discs. I recently rebuilt the motor with all forged components. Upon disassembly, with 180,000 very hard miles on the block, we checked crank end play. The reading was .0037. With 180K on the clock. After we rebuilt the motor with the new components, the reading was .0035. Perfect. So, after 180K and no crankwalk, what makes this motor, and the 1G seven bolts, different than the later 2G seven bolts?

The metal. The later 2G motors were made from a different composite metal alloy than the 1G 7-bolts and very early 2G's. I have been told that this happened when the block casting process was switched over to Hyundai. I have yet to see this proven, but it makes perfect sense. How do I know this? When boring the block, my machinist had found that the boring machine was taking significantly longer to cut my block, as well as the 1G blocks, than the later 2G's. This is because it is made of a different material.

I believe a weaker block alloy combined with the poorly designed check valves in the main galley is the primary reason why 1G 7-bolts do not walk nearly as often as 2G's.

Makes sense, doesn't it?


Matt.


It's my understanding that most all 95's shared the same block as the 1G 7 bolt. Am I correct, or did I just misread somewhere?
 
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