18RG Torque Settings??

[ganador]

the 88253 head should go onto the standard 18r(g variant) block no problems.
although there was a difference in pistons to accomodate for various compression ratio's over the years, the pistons have cutouts in them to accomodate for the valves,
so say you have a 18rg block (early block with big domed pistons)
ordinarily it would have an 88230 head on it, you can happily throw this head away and source a newer head, say an 88270 head from an efi 18rg
this head will happily sit on your existing block without any pistons fouling any valves (although i don't know of anyone that has actually got this most desired setup.)
there is a slight change in valve diameters i think between various generations of heads, but i don't think this is what you are talking about (ie changing the valve train from the 88250 head tot the 88253 head)

well when the head got rebuilt i think they took the valves out of the 88250 head and put them in the 88253 head so by that being done there should be no problems hey

[Steve M]

For setting up the rods and big end caps:

The "T" symbol on the rod goes at the front of the engine, always.
To orient the cap correctly, both the big end bearing locator slots (1 in rod, 1 in cap) go together on the same side of the rod.
e.g. in the case of the rod I'm looking at right now, from the front of the engine, both locator slots are on the exhaust side of the engine.
Yes, there also should be some matching stamp marks into one flat side of the rod to identify each cap with it's partner rod and also the correct orientation.

[Steve M]

River, which edition of the green book do you have?
My figures, matching 7MGTE MX73's, are from the 2nd edition English version, september1977 edition, which shows an 88250 head and adjustable cams in the photos.

[ganador]

yeah i figured out which way they went. i put a flash light up the bore and saw some motchers on the rod that match the ones on the cap.

[bholmberg]

I just changed a head gasket on my 18rg and tightened to torque specs as per recommendations above... The scan provided by RA35GT seems to be missing, so here is the one i've got... The head torque is lower than those listed by river, however my 18rg seems to be running fine with the head bolts 'overtightened' at 80 ft-lb (I wouldn't have tightened them that tight if i'd checked the manual first, my book says 52.1 - 63.7 ft-lb). Also if anyone needs the complete 18r(g) manual, I've got it all scanned up and am happy to send.

[Steve M]

WIth 18R-G engine, the main problem with over-torquing the head seems to be cracking.

The 88253 heads are particularly bad. I've seen a few of those with big cracks running front-back along a casting line.

When I say big, I mean 10 inches long!

88270 heads have much better casting in the problem areas, I've never heared of one of those cracking.

[bholmberg]

Thanks Steve, i'll be dreaming about cracks for the next few nights... i've got the 88253 tightened to 80ft-lb. would I be right in assuming it would have cracked by now if it was going to? (i've already done 1500km)

[Steve M]

If you've got oil foam in the top of your head then it is cracked.
If not, then it is not cracked.

Removing the cam cover or looking through your oil filler hole will give you some indication. The former, moreso than the latter.

[bholmberg]

all is good. I removed the cam cover and it all looks perfect. the oil looks just like oil. Next time i'll read the green book first.

[TTV8RA23]

So do these settings apply to the 18RGEU as well?
Thanks
Simon

[Steve M]

Yeah.
I can't think of any settings that should be different.

[TTV8RA23]

Yeah i thought so. Will use these settings. If there are any different it would be negligible anyway im sure!
Simon

[78celica]

Also if anyone needs the complete 18r(g) manual, I've got it all scanned up and am happy to send.

OOhh OOHhh yes please! I'd really appreciate it mate.