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Please Help! My Motor Is Possibly No Good :(

shaunzo101

By shaunzo101,
in Engines & Forced Induction

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shaunzo101 Enthusiast

shaunzo101

Posted
Posted

I have an R33 series 2 standard rb25det...everything on the motor is standard apart from pod filter instead of air box, and front mount intercooler.

I was driving along the highway tonight cruising along and all of a sudden the car started making this really fast knocking sound. I changed back a gear to see if it went away and it just made the noise louder and faster. I pulled over down the road and let it cool down a little, then tried to take off again, and it was gutless. It makes a knock knock knock sound at idle too, and if you put your head near the bottom of the motor you can hear it louder.

I called up my mate and he came down and had a look and believe it is the big end bearings? It was a mission to make it home because of how gutless it was, but i managed to nurse it home. I checked the oil in it when it had rested for a while and the oil was at the right level. I dont understand how this happened i was seriously driving along cruising at an easy pace not reving it hard at all.

I just need to know my options...should i look at getting the bearings replaced? Or change the whole motor, or better yet buy a long motor and put that in? What sort of money and procedures would i need to fix this?

R31Nismoid Grand Master

R31Nismoid

Posted
Posted

Well if it is bearings... AND you've then gone and driven on in...

rebuild time either way... and now your highly likely to have stuffed the crank as a result

take it to a mech that can actually confirm - via tow truck

shaunzo101 Enthusiast

shaunzo101

Posted
  • Author
Posted

A rebuild is definitely too expensive for me, even just replacing the bearings i think is going to be too dear considering i will have to get a professional to do it which could cost who knows much, unless anyone knows of a price on what this would cost to be done?

Is there any sort of guide on how to remove an rb25 i can follow?

NYTSKY Grand Master

NYTSKY

Posted
Posted

Disconnect battery.

Remove intake.

Remove clutch fan and radiator.

Disconnect cooler pipes.

Unplug all connections and label them (including ground wires)

Remove shifter.

Remove tailshaft.

Remove gearbox.

Unbolt engine mounts.

Lift engine out and and put it on an engine stand for disassemble.

Make sure you put all nuts and bolts in separate bags and label them.

GOOD LUCK!

Guilt-Toy Grand Master

Guilt-Toy

Posted
Posted
Disconnect battery.

Remove intake.

Remove clutch fan and radiator.

Disconnect cooler pipes.

Unplug all connections and label them (including ground wires)

Remove shifter.

Remove tailshaft.

Remove gearbox.

Unbolt engine mounts.

Lift engine out and and put it on an engine stand for disassemble.

Make sure you put all nuts and bolts in separate bags and label them.

GOOD LUCK!

after removing your engine and replacing it 5 times or so you just need one bucket for the nuts and bolts because you know where everything is :)

This guy is better off getting a replacement engine and getting it installed. Once you do this make sure you run very good quality oil. I suggest Motul.

tridentt150v Grand Master

tridentt150v

Posted
Posted

Get a mechanic to look at it first, not sure how much you or your mate knows about motors, but knocking sounds can come from a bizllion places.

Big end, cams, valves, lifters, clutch, gearbox, fan, alternator, basically if it rotates or moves it can make noise when it fails. You need someone that knows what they are looking at to assess your sound. Your first $100 could be the best money spent even before the repairs.

shaunzo101 Enthusiast

shaunzo101

Posted
  • Author
Posted
Get a mechanic to look at it first, not sure how much you or your mate knows about motors, but knocking sounds can come from a bizllion places.

Big end, cams, valves, lifters, clutch, gearbox, fan, alternator, basically if it rotates or moves it can make noise when it fails. You need someone that knows what they are looking at to assess your sound. Your first $100 could be the best money spent even before the repairs.

Im prety certain its got to be something inside the motor. My commodore made the same sound when i spun the big end in it as well, and it seized not long after making the same sound. Lucky for commodores it was only 600 for the motor.

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