26 replies to this topic

[LJ RB30]

The lack of oil pressure may not be fixed by using a different (external) pump!

 

What is the motor? fresh rebuild? old tired paddock basher? Stock? gazillion HP V8 eater?

 

The standard pump in good condition does very well in most stock to mild motors.

 

If your pumps in good condition your problem is gunna be else where & fitting some external job aint gunna fix it!

 

Need more info on your motor & exactly what testing have you done to think you need something else ?

[LJ RB30]

Well I can't say that I've seen too many if any exotic external setups for a red motor that's readily available!
Unless you do a dry sump set up

So the engine builders can't recommend a suitable oilling set up?

[RallyRed]

Hi Lastrites.....Im am no engine guru mate...but you may just want to hold off for a minute on the ext.oiler idea. There must be a 1000000 old red sixes chugging around that have had zero work done...or heaps of work done...all happily surviving on their ratty old oil pumps. As Bomber and co suggest mate...prob. best to pull it apart ( a real pain for sure) and understand the root cause of the issue.IMHO

[S pack]

So what's the goods on the existing oil pump. You may have mentioned it in your other thread but I can't remember.

[LJ RB30]

Time to strip it back down and check it all properly I recon. 

 

Up to and including .004" on the mains shouldnt cause any dramas. 

^^^^^ what he said

[N/A-PWR]

is a dry sump remote?

 

I see some dry sumps are lower down.

[grumpy xu1]

I think as the other guys have mentioned I'd be looking at asking the engine builder for the clearances 1st, if they add up ok doing a gmh oil pump rebuild, fitting a new electric gauge of good quality. See how all that goes, worse comes to worse crank & rods ect out & reset clearances, at least it doesn't use tty bolts. & as hutch said the liqui moly would be by far the best oil out of the lot hands down. I use their products whenever i can. Why not drop your oil, check it out & fit some & recheck pressure. You have penrite in it now dont you by memory ? It's worth a try ! Autobarn are a stockist. Liquimoly oil guide would be the easiest in the world to use as well.

[8BALL]

Who the hell is this "builder" ???
They cant give you clearances and tell you
- 'its good'
Yet clearly by all the threads its not good.

So nobody else wastes their hard earned $$$$$ with them, who are they?

[LC-GTR-1969]

I tend to agree that you should investigate further as to a) whether you are in fact getting low pressure- ie verify readings and 2) check the actual clearances.

 

My engine is built for nitrous but holds 20psi at idle, using JP HV pump.  

 

I would be looking closer at the source of the problem rather than bandaiding it. If it was an old dunger I would probably bandaid it but this is a new motor, that presumably you have paid good money for, hence you dont want to accept anything less than 'right' IMHO.

[S pack]

Hi Matt

 

Just trying to get my head around this. So the engine builder did the machining and yourself and the mechanic assembled the crank, rods, pistons, rings etc into the block?

[S pack]

By the way one of the measurements for a crush on a main cap was over 0.074 and that was just touching the plastigauge.

Holy crap, 74 thousands of an inch (0.074) would be like sticking your dick in a bucket.

[S pack]

I'm guessing 0.074mm ie. Closer to 0.003"

 

Ahhhh, that makes more sense thanks. I always tend to think in imperial measurements for mechanical tolerances & clearances etc.
 

He does say the bearings he bought are 010's which should be .010" u/s

[LC-GTR-1969]

I think you are on the right track mate. Dont name and shame at this stage- give them a chance to fix the problem.

 

Also, as a side note, never blindly trust that what a machiner has done is correct and accurate- they make mistakes just like the rest of us. One of the problems with machiners though, is that they also can seem ultra confident and tell you that ' it is right, your wrong, our work is always good, ive never had a problem in 30 years blablabla'... but in honesty, i have seen some MASSIVE issues caused by poor machining, or mistakes made during machining.

 

Ive had a block returned with the pistons sitting 2mm above the deck (I kid you not... and when I mentioned this issue, they said they had dummied it up  ). As soon as they saw this in person though, they were quite embarrassed... They massively over decked the block (big night out the night before maybe??). I have also seen them over bore/hone to way beyond clearances (triple to 4 times the spec I ASKED for). 

 

Every one of my engines that I have built has every bearing clearance measured with plastiguage, every cylinder measured to ensure its at the spec I specify and so on. Its an extra 15-20 minutes during a build, but think about how much money and time you spend building the whole thing, taking engine out and putting it back in, etc etc etc...