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

[andrewzuku]

I've made an attempt to remove the broken oil squirter from my head (the one that's meant to lubricate the top chain).

I bought a set of easy-outs and tried the #2 size with no luck, so stepped up to the #3. I've drilled a 7mm hole using the supplied reverse drill-bit and tried using quite a lot of force, but it won't budge. The steel bolt has really fused with the alloy head.

Has anyone ever used an easy out successfully? I can't remember having one work.

The spare Oil Squirter I have looks like 1/8 NPT thread. So my next plan is to buy the correct size "Q" drill bit (0.332") and then try to carefully re-tap the hole.

Is this a really bad idea?

[ra_28]

Are you using The tapered easy-outs? As they are shit, when they bite in they expand the bolt locking it even tighter into the apparent material. You need the straight shaft style, works every time for me.

I use the same style kit as in this link. (Using eBay for easy photo reference only) :-)

http://www.ebay.com/itm/25Pc-Screw-E...-/231176955233

[andrewzuku]

Thanks for the suggestion. I just bought one of those kits - but didn't get to use it. When I drilled out the bolt to 8mm for the straight-flute "pin" it walked a little off center. I'm left with a crescent-moon of the old bolt, still not budging.

I'm going to try to re-tap the hole (1/8 NPT).

[andrewzuku]

The cam tools are done

I got 6 made within the minimum order of $110. So they cost me $18.33 each.




Now that I have one, I realise I don't quite know exactly how to use it. Obviously the little tab goes into the notch like in the diagrams...

... but am I aiming to have the tool perfectly centered sideways between then two cams?

Ian and Peter, PM me your addresses if you're interested. I'll send you my PayPal account and the price including shipping.

[ra_28]

Hey Andrew

I'll take one as well.

Alex

[Nevakikamukau]

Thanks Andrew

PM sent

Cheers

Peter

[andrewzuku]

Oil squirter success!

I got my 90mm long 1/8 NPT tap today. When I went to use it, the remaining sliver of bolt came loose

The 8.5mm hole I'd drilled was a tiny bit off-center, so now that I've I re-tapped (more like cleaned-up) the thread, the new bolt doesn't tighten down as snuggly as I'd like. I'll use some loctite thread lock liquid (the red stuff).

I was very careful using oily rags to not let anything drop onto the chain or into the sump.

To clean out any metal in the oil galleries, I've run a rubber hose from the hole into a bucket and turned the car over with the starter for about 30 seconds.

As an extra precaution, i'm going to do an oil change with some cheap oil and filter, run it for 10 minutes and change it again with good oil (Penrite HPR30) and one of the following genuine Toyota filters (whichever I can get):

• Genuine 18R-G: 15601-33021 (longer)
• JZ series: 90915-YZZD2 (shorter)

Should that be enough to get any metal shavings I've missed?

[Omegaman]

maybe buy a sump plug with a magnet on it, i think there available.
that should tackle any shavings over and above. congrat's

[stidnam]

I'd be using the best filter that you can for the from 10 min as that is where most of the metal bits will be floating around with your oil. Filters are designed to remove crap so don't skimp on the filter for the period where the engine will be most susceptible to wear.

[andrewzuku]

Hey Stidnam, Good point. I'll fork out for a better filter for the flush too.

Ok, now onto cams...

I wanted to measure my regrinds before taking them out.

Using a degree wheel and dial indicator I measured maximum lift: IN = 473.25°, and EX = 255.5° (on the crank).

For street use, Clive Cams say intake centerline on their 273A regrinds should be IN = 105°, and EX = 111°.

Intake centerline is crankshaft degrees ATDC, while exhaust is crankshaft degrees BTDC. So on a 720° cycle starting at ignition:
IN should be 465° (360° + 105°)
EX should be 249° (360° - 111°)

Which means, my intake cam was 8.25° too retarded, and exhaust cam was 6.5° too retarded.

[Laz]

Peeps, I've got a question (and I swear to god that i've done searches and didn't come up with anything...)

The very first post on this thread from the honorable "The Witzl" has led me to believe for a long time now that the 88253 head was the first to get double valve springs.

I've currently got x4 heads, first is a 253 with oversize valves from an unknown maker that to be honest are a bit buggered, so stripped it down and found the double valve springs as expected...

Second is a 250 with TRD big valves, I stripped this one to recover the valves to put into the 253, but discovered this has double valve springs too so I started to wonder if this head has had some other work done to it other than just the big valves.

The third head I stripped was a completely boggo standard 250, I only took it apart to recover the bucket shims to give me some choices for these when rebuilding at least one of the big valve heads, but went on and removed the valves while I was at it as the head itself is in very good condition and is worth refurbing as a spare part for the shelf.... this boggo standard head has double valve springs too....

Forth head is still on a built up engine and haven't looked at it yet, but it's a 250 as well...

I did have a scan through Rivers Mammoth 18R Diagram Thread...

http://www.toymods.org.au/forums/tec...ine-specs.html

... and found at figure 22 that the 18R-GU (7510-7707) is clearly shown as having single valve springs, but at figure 23 shows an 18R-GU (7707-7707) (one month!) with double valve springs, I assumed this short run of 18R-GU heads were the 253's, am I wrong???... was there a short run of 250 heads made with double valve springs???

Another thing I've found on both of these 250 heads, but not on the 253, is a number stamped into the flat top of the therostat housing mount/lug/boss/thing on the side of the head, the TRD big valve head has 37479, the other boggo standard has 37749, any ideas on what this is???... the stamping job looks a little bit amateurish i.e. the line of numbers aren't perfectly straight with each other, so may have been done off the production line??

Any thoughts or knowledge on this?... have I missed something and all of the 25* series have the double valve springs??

Tried reading through this thread again from the start but got to page 36 before I thought "bugger this, it's taking too long" and asked the question instead, might be time to whittle this thread down to just the gems of info.....

[Steve M]

Laz,

I also bought a second hand head with TRD big valves in it.
I think the head was kitted out with a TRD valve and spring kit.

These items looked different from standard.
Valves (oversize)


Springs (no markings but I think they looked different, uniform coil, not progressive like standard dual springs).

Retainers provide more compression than normal and appear different.


Under spring washers were different (machined metal rather than pressed metal)


Maybe your head has a spring and retainer kit too.

[Laz]

Thanks Steve,

From this I can tell that the otherwise standard 250 has just had the standard 253 double valve spring package fitted, progressive springs, thin pressed lower seats, upper caps look a little different to both those in your pic, they are plain flat topped.

I'll check the TRD Valved 250 & 253 head parts in a bit and report back.

+rep coming your way sir...

[Laz]

Ok...

TRD Big Valve 250 head appears to have the full selection of TRD parts, uniform coils, machined lower seats and the extra compression upper caps.

The 253 head also appears to have the same, but the workmanship to get the bigger valves into it looks to be a bit sloppily done so I'm going to recover all the valve bits and rebuild the 250 for my engine.

Other than the 10mm exhaust studs, is there any other differences between the 250 & 253? The ports on both heads have already been worked so there is no difference between these particular 2 in that respect...

I grabbed some photos to illustrate the differences between the standard double valve spring set-up and the TRD version, first up is the standard set-up...





These are the TRD items...





Here's the underside of the retainer caps, TRD on the right...



I also scanned the relevant pages from a TRD Catalogue from 1988 that I've got showing the part numbers of all their items for the 18RG, thought this might help others identify if they've got any TRD bits...

[andrewzuku]

Great Success!!

I just put 88230 cams in (thanks to Willowfan), re-shimmed, and went for a test-drive.

Click for YouTube video with that lovely 18R-G sound:


The engine now runs much smoother throughout the entire rev range, and is a LOT quieter on idle (no misfire either).

It's still running a little rich here (trying to compensate for a flat spot). AFR = about 11:1 on idle, and 12:1 at full noise.