Jump to content
SAU Community

Recommended Posts

Ok so I finally have an RB25DET sitting in the garage waiting patiently to be installed into the ceff... The wrecker I bought it off had reason to believe it had been sitting for maybe a year, some of wich was outside not under cover. It's also unclear to me if the engine was properly sealed i.e inlet and exhaust plugged up.

When he first did the comp test the engine was hard to initially turn over, then showed some irregular results 145-165.

After a few more rotations it showed 165-170.

My questions are these-

Is it likely that there was some form of corrosion build up in the bores from having the engine sit unused for so long? Will this burn off without any harm to compression? should the engine be 'free' enough to turn by hand?

not good if rain was getting inside the engine, but if the compression numbers are up around where they should be, it must have been fairly well protected. how bad is the corrosion on the motor?

Pull the motor down

Only way to tell.

If it's corroded, it's a bad engine, basically, throw it away.

My uncle bought a 1UZFE and couldn't bore it enough to get rid of pitting that the water did to the engine.

I'm not really worried about actual water droplets getting into the engine... More so that it was left to 'breathe' if you will. There is a little bit of that white chalky corrosion on the aluminum parts like the inlet manifold and front cover on the turbo.

What would the reason be for the initial comp test yeilding bad results, and the second one very good results? Crud around the top of the piston and rings?

Am I worrying too much? lol

was the compression test done with the motor hot? compression tests cant be done on a cold motor as the readings are inaccurate. has to do with the expansion of the metal rings, pistons and block. May be why the results varied....

initial ones prob had no oil presure, then slowly as it built it got more *relative* if you will, either way i bought an rb20 in such condition, held just under 200rwkw awsum compresion, unless there was actual water in the bores and left to fill up/sit there with it in, i doubt you will have much troubles.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • I read this and thought "ah! I will do this scissor jack on the tow point thing!" I just use my floor/low profile/costco jack and lift the car up by the tow hook itself, then slide jack stands under. Never thought about using scissor into floor jack combo :p
    • Well, my new WMI system took much longer to finalize. I actually missed my dyno appointment last Friday and lost my 150$ deposit. I'll be going back in the next week or two.  To sum it up. I only kept the AEM tank from my old setup. I replaced the AEM pump with a higher flow/pressure ProMeth 30GPH pump. I also swapped over to a 6AN low pressure feed line to the pump from the tank. There's also a pressure switch you cannot see on the pump high pressure line.    This is feeding 6x 200CC direct port nozzles and 1x 500CC Pre Throttle body nozzle. All fittings are Swagelok, because well why not. I also have a 300PSI pressure sensor up front.    I now have my Haltech ECU controlling everything. I start my pump with a basic relay at 5PSI and deadhead it. I then PWM a 3000CC methanol Injector to control flow starting around 10psi. The pressure switch in the trunk, along with my tank level are safeties before I ever get to 10PSI, and then I use my pressure sensor upfront as a secondary safety to cut the WMI and corrections in case the injector blocks or a line ruptures.  Wish me luck on the dyno!    
    • So, I'm back with bad news. There's no jack long enough on this planet that will reach the front subframe. If by some chance there is, it would weigh 200lb's.  I purchased a long reach jack... The damn thing weighted 120lb's and was massive. Didn't even come close, was still short at least a foot. It was a pain, but I brought it back. Next I decided HA! No problem, I'll get an Extra long reach jack. Well, I couldn't lift the box... It must have weighed 160LB's and luckily there was an open box in store. I took measurement and was still nowhere close.  Sadly I've lost hope and have accepted defeat. 
    • Thanks for that tip, niZmO_Man. I think the battery is OK. It's quite a new one, but I'll check. Last time I needed a new battery, everything electronic was fine, except that there wasn't enough current to turn over the starter. I decided to order one of the partial AV system translation CDs from Car Audio Workshop in NZ. That might have some effect, or help me diagnose the date problem. 🤞
    • I suppose it was relatively stock too, the JZ motor handle most mods thrown at them without even breaking a sweat 
×
×
  • Create New...