For the love of a tractor engine: The life and times of the 18R-G

[Roscos]

So does that mean I have an 18R block?

I said if the engine starts with 18R 95xxxxx it's a twin cam block. I have 2 of them, 1 early, 1 late model.

An 18R 96xxxxx as some else states they have is a 18RGUE l don't know but if it is an 18R block l would imagine they are the same..

The 95xxxxx engine number is what l think toyman75 stated as a T/C block.


Roscos

[crowncustom]

For starters you have an RG block and the easiest way to tell between 18R and 18RG is that the RG has the engine number stamped upside down like the one in the pic and 18R is stamped the right way up.
Cheers Brett.

[bholmberg]

I breathed a sigh of relief when I discovered today my block is an 18rg... thanks for the info to help with that discovery!!! - this 'life and times' thread is full of gold like that.
ANYWAY.
i'm up for an oil change... just thought: before I go buy oil, I'd ask the question...
What oil do people recommend for these engines?
my 18rg has done about 2000k since rebuild if that makes a difference
I was going to fill it with Valvoline xld premium 20w-50, just cos i've got some laying around.
Any suggestions?

[o_man_ra23]

I use Penrite HPR10. I find it a good oil in the 18R-G, and the couple of oil comparison tests I have seen always seem to have Royal Purple as the #1 performing oil, the brand who sponsors the test as the #2 performing oil, and Penrite as #3.

Personally I am not a fan of Valvoline, however others (including John Laws) may well disagree with me.

[bholmberg]

thanks O_man... I'll give the hpr10 a go.
I might also try and build up some sort of spreadsheet over the next few years with temperature vs. rpm vs. oil pressure to see if I can make an educated analysis...

[StuC]

i only ever used Valvoline single weight 30 run-in oil, i dont like their other stuff. Very happy with HPR10 on the cars i ran it in.

[o_man_ra23]

I'll probably go SIN 5 oil in the 18R-GTE now that she will be running Arias forgies, as the tighter clearances will enable the thinner oil to work properly. Just the oil pump I need to worry about with that - hopefully the extra volume remake will be moving forward soon though...

[vpatrol]

I'm ever so slowly trying to rebuild an 18rg for when my ra40 arrives from Aus. I'm planning on swapping it for the 18R currently in it. I've never rebuilt an engine before and the RG I bought was completely disassembled.

I finally borrowed some vernier calipers and had a measure. The numbers from the block I got are (from front to back) 88.47, 88.55, 88.54, 88.51 (subject to error with my inexperience with calipers)

I also measured pistons. They are 9.7's and they seem in pretty good shape. My measurements for them are 88.41, 88.47, 88.4, 88.4. Also subject to measuring errors.

When buying new rings, what size should I be looking for? I'm not looking for monster power and have no plans on huge upgrades to the motor. Just a power up and what I originally had in the car.

The cylinder bores were also in good shape in my opinion. I could not feel a lip on the top of the cylinder and there were no scratches/gouges etc. Would a simple hone suffice or should I be aiming to have the cyclinders bored to the exact same size?

Cheers

[o_man_ra23]

Verniers aren't the right tool for measuring bores. 88.5mm is the standard bore size, so standard rings will work (18R-C items are correct fitment for those pistons). Generally a good hone and re-ring should see you through if the bores are in good overall condition. I wouldn't do that if you are after a monster engine, but if you just want a fairly stock 18R-G with some freshness to it, then you should be on the right track.

Photos would be good. If you aren't certain about the measurements, take them to a machine shop, have them measure for you, and check the bores for out-of-round prior to honing. The measuring shouldn't cost you much at all, if they charge you for it at all.

[Sagluren]

the out of round issue is a good one to look out for.. i have been done by it and there is nothing worse then the first startup and seeing smoke out the rocker cover..


cheers sam

[Mr DOHC]

Just putting this out there

is there any interest in 12.5:1 ratio pistons, i have one here and am happy to have it used to get more made.

just throwing it out there

[RA35GT]

Just putting this out there

is there any interest in 12.5:1 ratio pistons, i have one here and am happy to have it used to get more made.

just throwing it out there

Hrmm, whats the ballpark man?

[Mr DOHC]

U mean how much do I want?
Nothing, but I won't send it anywhere unless there is sufficient interest as it's quite rare and I don't want it getting lost. I think it's an Arias piston designed for methanol for 80's speedway cars

[o_man_ra23]

Arias can still make them new for around US$500 plus postage. Paradise Racing in California was the cheapest I could find for them. You tell them what bore size and compression ratio you want and whether they need to be suited to forced induction, nitrous, or aspo. They supply them with rings, pins, and pin retainers.

[RA35GT]

Sorry mate, I thought you already had sets made previously and were doing another run. LOL

I do need some high comp pistons to suit upcoming mods however.