DraygenX

I'm trying to install an RB underdrive main pulley but can't crack the retaining bolt. I'm affraid to pull out the breaker bar and really put some *** on it. 1 because I'm not sure if that will damage the engine rotating backwards like that and 2 I'm affraid I might crack off the head eventhough it's a new engine. any suggestions ? I've tried to use an impact which was putting out about 900lbs/tor. and it still didn't do it.

J-Rat

iTrader: (2)

If your talking about the main bolt that is in the center of the main pullies, thats your E-shaft bolt. You do NOT need to remove that to get your main pullies off, you need to remove the 4 bolts on the periphery of your main pulley.

Removing that E-Shaft bolt without pre-loading the clutch will cause your Torrington bearing to fall and will ruin that shiny new motor of yours.

Rat

rotaryracer1

iTrader: (1)

if you have to take out the e-shaft bolt make sure you have someone in the car holding the clutch down the ENTIRE time or prop it with something of course.

DraygenX

yeah the instructions from racing beat note a few times that the clutch has to be in. and j-rat you're thinking of the power steering pulley and the ac pulley, the bolts gotta go to get to the main one, just the damn thing won't break loose

ddub

With the RB main underdrive pulley you have to take the hub out, the RB pulley has a built in hub, so the E-shaft bolt must come off.

Take precautions to have someone hold the clutch in the entire time otherwise you risk other problems, look on mazdatrix they have an article about it.

ddub

No what he said is correct, I just don't think he realizes the RB pulley replaces the hub. The main pulleys can be unbolted from the stock hub just like the AC and PS pulleys. But for the RB kit, yes the hub must be taken out as well via the E-shaft bolt.

J-Rat

iTrader: (2)

Either way, you pull that E-shaft bolt without pinning the clutch and life sucks.

Underdrive pullies are someting that will never get installed on my car..

ddub

They aren't as bad as you think, I've had mine on for a long time now with absolutely no problems. Temperatures stayed the exact same and everything.

But yes, have the clutch in the whole time otherwise you risk ******* up some things. I had my engine out and vertical when I did mine, so it wasn't a problem.

DraygenX

the engine has less than 5k on it so I'm not taking any chances, but i guess it's time to get out the breaker bar and buy someone a case to hold down the clutch. is counter rotaion on the engine going to effect it at all? I started to get down on it but I was having an issue keeping the engine from rotating

ddub

Don't try a breaker bar, just use an impact gun. Put the gun on it, press hard while using it, get one with as much torque as possible and if it still doesn't work just overdrive it with higher PSI than it's rated for (I do this all the time, it's no big deal) and it should come off easy. Mine took about 30 seconds of constant gunning to before it came off, and that was after I tore apart an adapter. Impact is the best idea.

DraygenX

tried the impact route cause I agree it's the better way to go. I guess I need one with alittle more *** cause it wouldn't break even after a can of wd40. I think I was only getting about 400torque eventhough the mac guy says it's rated at 900

ddub

What PSI rating? Try overdriving it. So if it is rated at x ft/lbs at 90 PSI then run it at like 120 or 130 PSI, see how that helps.

DraygenX

As far as that goes, I have an underdrive alt. pulley and have removed the clutch fan with an electric and I swear it did wonders, runs cooler, gained probably 10 to 15 hp easy and never had an issue except for low power at night wich I fixed with a deep cycle blue top, only thing left is getting the idle fixed which is low but I don't think it has anything to do with the pulleys. have a feeling it's a sensor or something

DraygenX

I was running it at 120, it's rated at 90

ddub

Just FYI, you didn't get 10 to 15 hp from an underdrive alternator pulley, no way possible. You wont even get 10 to 15 with the alternator and main underdrive pulleys, it just wont happen.

Also, an underdrive main pulley will further underdrive the alternator, so be careful with your charging system since the FC charging system is already pretty shotty.

DraygenX

Well between, the fan and the underdrive alt. I know it free'd up a good bit of the load on the engine, maybe the increased throttle response is the most noticable. maybe the hp was alittle high but hey anything noticable it a good thing! lol. Power on the car's good, I've redone all the grounds, and run direct ground to the leading and trailing coil as well an additional 4 gauge lead from the - on the battery straight to the frame. Seems to be holding up well, my low idle seems to be the biggest issue

ddub

Hmmm, that sucks. You can try renting a higher torque one maybe.

DraygenX

didn't even think about renting one, good call! The snap-on guy of course wanted $300 plus for a 1000lb+ torque one

88 GTU

try pb blaster and let it soak in for a while and keep hitting it until it stays soaked then try the impact gun again or heat it

DraygenX

there's another thread going that someone heated it and it worked, i wouls have assumed heating the nut would expand the nut making it worse but I'll keep that in mind for a last resort. I believe this is the other thread https://www.rx7club.com/2nd-generation-specific-1986-1992-17/help-front-pully-bolt-406872/

fc3s91

iTrader: (23)

The reason you are having a heck of a time is because factory puts red locktit on there thread. I have heated them up before but you have you watch out you don't melt the front seal. I also fill the inlet of you impact with impact oil, then connecting it back on the hose and impact away.
Thanks Robert

J-Rat

iTrader: (2)

Underdrive pullies are just like any other mod.. Some people do them some people dont. I dont need to take any cooling chances with my FC in Tucson heat. No underdrive pullies for me.

Now I do run an electric fan.. That would be a $250 Black Magic fan on a K2RD radiator.

ddub

Yah I hear ya. I took a chance with the cooling issue and so far it's good. We'll see how it is this summer, and then after I go turbo :|

Might have to switch back later when I have a hybrid with 13 lbs running through it and a big FMIC

J-Rat

iTrader: (2)

Already got all that...

rrx777

10 or 15 hp from a under drive pully? I dont know what kit u got but mine only gave me 2 or 3 hp u sure thats right?