ughh, sighh. now i get to play the waiting game.

[cote006]

so my car developed a bad rod knock the other day. filled it up with oil and it disappeared. i knew it didn't fix it, but it gave me reassurance. came back yesterday on my way to bringing it to the shop to have the starter looked at. unfortunately today when i went in to answer some questions for the guy looking at it, he asked me about the knock i had previously described. i decided to show him it, started the car up, much to my surprise, absolutely no knocking sounds at all, except for a split second on the initial start up. so then he decided that it was highly doubtful but still possible it could just be some carbon build up. we spray some atf in the engine to break any down, then almost immediately it came back. the knock was louder than ever, and once he put the hose back on the 3000 pipe, it got worse and worse. within a matter of two minutes, it was knocking and rattling as if there was no tomorrow. honestly i'm surprise a rod didn't come shooting out. So now it sits at his shop collecting dust. we'll eventually trailer it or tow it home. but until then, the guy said he wants to poke around at it and figure out what exactly is rattling around. he said he's never heard anything like it in all his experience with fixing cars, which i find surprising because it's what he's done his whole life and he's in his 70's or so.

how great though, right? now i get to just sit here and stare at it for 2 months until i ship out to Basic and AIT. At least once I come back in december i'll have the money to fix her.

just some questions though. How many of you would recommend upgrading from the 7mgte to the 1jzgte? is it a difficult swap?
as much as i hate to ask, what's the difference in reliability? i understand that an engine is as reliable as the owner, depending on how well it's maintained and everything. For my personal use, I want something that can handle good power mostly stock, but still reliable. I haven't done much research on the 1jz, so i'm not too knowledgeable on them, but from what i understand the 7m is still a great engine if maintained.

anyway. i still have about 9 months to make up a decision. let the wait begin, i guess.

 

[jake8790]

I had to make the same decision. I'm building my 7m. For me, I'd rather have a fresh 7M that I personally built than a used 1JZ. I also prefer the sound and the torque of the 7M. I also hate wiring. It depends on what you want out of the car, and your skills involving mechanical work and wiring.

 

[gsxr141]

+1. i'd rather spend the money on building the 7m, than spending much more swapping in a used motor.

 

[cote006]

thanks for the input! yeah, it's a big decision. i honestly have no idea what kind of damage the 7m that's currently in it has. i have a feeling it probably has a lot more than i would like to think it does. for all i know, the whole thing could be shot and not be at all worth rebuilding. hopefully the guy who's taking a look at it can figure out just how bad of damage it has. all i know is that knock and rattle did not sound good at all.

 

[RogueCustoms]

For me... I would like to do a hybrid... Some sort of 1j and 2nite combo... Or a 2j all the way. But.... Here lies my problem. I suck at wiring... And I'm only ok with mechanical. So I've stuck with my 7m. Not only that. How much more fun will it be to bet through DEQ?

 

[cote006]

also another thing that I have to take in to account is that no matter what I do is going to cost me more because I personally am not going to be doing the rebuild/swap whatever I choose to do. I'm going to have to bring it into a shop. And if I decide to go the 1jz route, or if I get a used motor in general, I'll have it looked through to just to make sure it's not beat to hell already. I wish I had more knowledge and skill with mechanics. Unfortunately for now I'm going to have to have my brother in law, who is a mechanic, help with most of the minor stuff. He's been showing me what's what and how to replace some things. But as far as any rebuilding goes, the shop he works at is unable to do because they don't have machining equipment. Eventually I'm planning on switching my MOS in the military to some sort of mechanics so I can get that training for free. While yes it's true that most, if not all, military vehicles are diesel, and it will be different than working on these kinds of engines, but it's still knowledge, and will be of some sort of benefit.

anyway. what are some benefits and disadvantages to both the 1jz and the 7m?

 

[RogueCustoms]

The 1jz doesn't have the head gasket problem the 7m does. Easier to get HP out of it. Higher reving.

Although, I'm pretty sure its harder to get parts for since it was a Japan only motor.

Look around here on the forum. Look up some of the moderators in the 7m and the 1jz sections. They'll help you out.

 

[onemancrew]

Sure the knock isn't just something simple like a loose harmonic balancer or something? Along with a hidden oil leak somewhere?

 

[whitehat89]

what are some benefits and disadvantages to both the 1jz and the 7m?

Power wise, the 7M has a longer stroke, so you will have more torque with (stock) a lower redline. The 1J has a shorter stroke so it revs higher but doesnt have as much torque. Also, as RogueCustoms said, the 1J (and 2J for that matter) come from the factory with a metal headgasket. However, parts for it arent as hard to get as you might think, ESPECIALLY when it comes to aftermarket. The 1J stock bottom end is good for 600ish HP, iirc. The 7M can make a good amount of power on the stock internals, however, you need to really take care of a 7M, it's not a motor you can just upgrade and start thrashing away on.

As for the difficulty of the swap, I've been researching it for my car for the past 9 months. Basically, if you have a 89+ chassis, the mounts are the same, otherwise BIC Performance sells adapter mounts for 86.5-89. The real pain is going to be the wiring. Dr. Tweak at Phoenix Tuning is highly recommended, does awesome work on wiring.

Here's a list of really good stickies to get you up to speed on what you are looking at! http://www.supramania.com/forums/images/icons/icon6.png
http://www.supramania.com/forums/showthread.php?119858-1JZ-Swap-Parts-Into-a-MKIII-List
http://www.supramania.com/forums/showthread.php?153102-Your-1JZ-GTE-And-2JZ-GTE-Swap-Guide-For-Dummies
http://www.supramania.com/forums/showthread.php?43888-**How-to-wire-a-soarer-1JZ-into-MA70**

Hopefully those help you out.

Also, about the sound, the best info you could provide for us to try to diagnose is where the sound is coming from. Top of the motor, bottom, front, back?

If any of my info is incorrect, someone please correct me.

Also, as an ex-service member (Air Force), thank you for your service. Seriously.

 

[cote006]

The 1jz doesn't have the head gasket problem the 7m does. Easier to get HP out of it. Higher reving.

Although, I'm pretty sure its harder to get parts for since it was a Japan only motor.

Look around here on the forum. Look up some of the moderators in the 7m and the 1jz sections. They'll help you out.

Power wise, the 7M has a longer stroke, so you will have more torque with (stock) a lower redline. The 1J has a shorter stroke so it revs higher but doesnt have as much torque. Also, as RogueCustoms said, the 1J (and 2J for that matter) come from the factory with a metal headgasket. However, parts for it arent as hard to get as you might think, ESPECIALLY when it comes to aftermarket. The 1J stock bottom end is good for 600ish HP, iirc. The 7M can make a good amount of power on the stock internals, however, you need to really take care of a 7M, it's not a motor you can just upgrade and start thrashing away on.

As for the difficulty of the swap, I've been researching it for my car for the past 9 months. Basically, if you have a 89+ chassis, the mounts are the same, otherwise BIC Performance sells adapter mounts for 86.5-89. The real pain is going to be the wiring. Dr. Tweak at Phoenix Tuning is highly recommended, does awesome work on wiring.

Here's a list of really good stickies to get you up to speed on what you are looking at! http://www.supramania.com/forums/images/icons/icon6.png
http://www.supramania.com/forums/showthread.php?119858-1JZ-Swap-Parts-Into-a-MKIII-List
http://www.supramania.com/forums/showthread.php?153102-Your-1JZ-GTE-And-2JZ-GTE-Swap-Guide-For-Dummies
http://www.supramania.com/forums/showthread.php?43888-**How-to-wire-a-soarer-1JZ-into-MA70**

Hopefully those help you out.

Also, about the sound, the best info you could provide for us to try to diagnose is where the sound is coming from. Top of the motor, bottom, front, back?

If any of my info is incorrect, someone please correct me.

Also, as an ex-service member (Air Force), thank you for your service. Seriously.

Thank you both for the great advice! I will definitely dig into those!

As far as the knock goes, from what I can tell, it seems to be more bottom frontish. we haven't taken a stethoscope or anything to it yet. just haven't had the time. so thats all i can tell from just listening to it from right in the engine bay. The guy I bought the car from who put the engine in it said that he was almost 99% sure that it wasn't a rod knock because it never made the noise in the car he pulled it out of, and only started the moment he dropped it into the 86.5. the engine came from an 89. He thought it was something to do with the timing because the engines timing is horribly off. but from the sounds it's making, i dont think its anywhere near that simple. But hopefully our friend who is taking a look at it will be able to figure out what it is. I'll be sure to let you guys know in this thread when i do get it figured out. Most of you will know better than me. As far as the oil leak goes, I know it's leaking oil. traveling from my Dad's house to my Mom's house it would go through 5 quarts of oil, and the trip is only an hour and a half. The valve cover leaks quite a bit due to the fact the previous owner over torqued it to try and get it to stop leaking at factory torque settings, but only made it worse, he also said he's sure the front seal on the bottom end is leaking as well. That's where it seems to be leaking the most. Fortunately it does have a MHG in it already, but I'm not sure if it's going out or not. I would hope not as it's fairly new, but I did notice there's oil mixing in with the coolant in the coolant reservoir, at least I think. I just know that a few days ago i checked the coolant, all looked fine and green like it should, just kind of low. I added coolant, then the next day I checked it again just to make sure it wasn't leaking, and thats when i saw it looked like real light foamy coffee.

 

[AJ'S 88NA]

Something with the timing?? Could be the crank pulley comming apart, would also cause the knock. Check the rubber band/ring on the pulley.

Just saw the front seal is also leaking, if the crank pulley is bad the main bearings are probably "hammered".

 

[GrimJack]

Diagnosing a rod knock is easy. If you start the engine and pull the plug wire on the injured cylinder, the sound goes away.

A loose front damper pulley makes the same sound. So does a loose flexplate on an automatic.

 

[cote006]

Diagnosing a rod knock is easy. If you start the engine and pull the plug wire on the injured cylinder, the sound goes away.

A loose front damper pulley makes the same sound. So does a loose flexplate on an automatic.

couldn't be a flexplate, its a 5 spd. but, i've also noticed that since the knock got louder, it seems to have lost some power. when accelerating in mostly just 1st-3rd gear, it feels like it's slipping per-say. not like a transmission slip, but like as if the engine stops giving it more power, and just stays in place for a split second, than catches itself again and accelerates more, and repeats this until about halfway through 3rd, then stops and runs normal, just with a loud knock.

 

[GrimJack]

I'd suggest *not* driving it until you figure out what is causing the knock. If it really is a rod bearing, fixing it now means replacing some bearings and polishing a crank. If you keep running it, you can add a set of rods, pistons, and a new block to that.

 

[cote006]

I'd suggest *not* driving it until you figure out what is causing the knock. If it really is a rod bearing, fixing it now means replacing some bearings and polishing a crank. If you keep running it, you can add a set of rods, pistons, and a new block to that.

yeah that's why it's just sitting in the guys garage right now until he's finished looking at it, then we're going to trailer it home and let it sit until we figure out what is going on with it. My gut tells me its a rod, but i can only hope it's something easier than that.

 

[whitehat89]

If you have oil in your coolant, that suggests that you have a BHG. Did the motor have a MHG when you got it?

Also, the location of the noise leans towards the idea proposed by "AJ'S 88NA".

 

[cote006]

If you have oil in your coolant, that suggests that you have a BHG. Did the motor have a MHG when you got it?

Also, the location of the noise leans towards the idea proposed by "AJ'S 88NA".

Yeah when I bought it the guy had said he had just recently put a MHG in it, and had never really driven it much. It was his project car originally. He upgraded to the MGH, got the engine in and got the car running, then decided he wanted a different supra to build, so he stopped building this one and decided to sell it. and here I am with it. So I know the MHG is fairly new.. I'd say at most probably like between 7-9 months? I would hope it would have lasted longer than that, specially if it wasn't driven ever. I'd like to think it didn't really get driven all winter. Is it possible that being as it leaks oil from a few places, it could have just snuck in there? I keep an eye on the temp gauge all the time just because I know these engines like to blow head gaskets, but the temp gauge reads that it's pretty normal. It could very well have a bgh though. I also know that he took the top end of the engine in to get rebuilt recently, before he sold it to me.

 

[Dylan JZ]

The 1J stock bottom end is good for 600ish HP, iirc.

Actually, it has the same potential as the 2JZ-GTE.

 

[whitehat89]

Actually, it has the same potential as the 2JZ-GTE.

Correct, that's what I've been told, I was using a conservative number for a tad more reliability, I have a habit of overbuilding my engines.

 

[tyang82]

sounds like my old supra. it now sits and collects dust while i drive my 91. my rod knock is very bad. maybe the previous owner didnt do the proper work needed to put the metal head gasket on. I'd say use your money to rebuild the 7m. i was once thinking like you about the JZ stuff but thinking about the expense, i rather rebuild my 7m and get the monster out of it.