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

[The Witzl]

NVM my previous post... it was the timing.. we have 18RG + EFI Liftoff!

told you so

[Steve M]

Just thought I'd add something about measuring shims for replacement (read - reground) cams.

When measuring the valve clearances so that you know how think your new shims have to be, there's something to be mindful of:

There must be a shim under the bucket for the whole process to work.
The height difference from the protrusion on the underside of the bucket to the main bucket top underside is less than the difference between the top of the valve stem and the top of the valve spring retainer.

Basically, this happens if there's no shim in there:
You measure the clearances, you order the shims, you get the shims and they are all too thin.
The top of the retainer hits the bucket, but not where the shim sits.

I'm 98% sure that what I just wrote was really hard to understand for a lot of people, but when you put in reground cams (weld 'n' grind especially) make sure you remember to stick a shim in there or you'll waste your money every time.

Measuring up the shim clearances for base circle regrinds, it's a lot easier to just stick in your standard shims and then check the clearances. Weld/grind set ups may be different depending on how much hard facing was done.

[bigmat]

witzl what is the furthest you could push a stock 18rgeu in stock form turbo'd. this is with ball bearing turbo, aftermarket ecu, good intercooler, injectors and exhaust. reliable power for now.

[rn41leroy]

sorry just resubscribing to the thread! take it like a bump haha

[tricky]

Does anyone know if there were water pumps on 18R's with different sized outlets? I've had two lower radiator hoses, both gates I think, that are loose enough on the water pump to allow a sizeable leak, so they need spacing with smaller diameter rubber hose... Previous hoses have been fine... Could just be a case of a company not giving a shit because it's old and japanese

Another problem along the same vein. I got a gasket kit which didn't include the block-filter mount gasket... What material was the original gasket made from? My homemade paper gasket didn't particularly like the oil pressure and has deteriorated in performance somewhat

Karl, I'll take a punt and assume that your PCV valve is the elbow joint on the cam cover vent? Have you ever had any problems with erratic idle due to sticking of the valve etc? With that setup, you'd be at the mercy of perfect gasket sealing and SFA blow by too... I like it, but I can see potential problems

[The Witzl]

Tricky,

No, that 90* elbow is just a plain metal elbow... not the PCV valve. The cam cover itself has the PCV valve in it AFAIK. Don't forget also that the fitting on the plenum that hose goes to is actually routed to in front of the throttle butterfly.

I have actually been getting the odd idle problem here and there, which *could* be from sticking valves, but it could also be from the tuning of the Megasquirt-II not being finished.
There is also a one-way valve on the block vent too, i dont know if that makes a difference?

Can you explain why I would be at the mercy of perfect gasket seals? I cant quite work that one out?

PCV systems are still a relative unknown to me, so if you have better suggestions i'm completely open to them



As for the water pumps - there are about 3 or 4 different types of water pumps that I've seen in catalogues to suit 18R's. I've not had a problem with any of mine and radiator hoses i've bought from Supercheap.

The Oil filter mount gasket is paper in the kits i've bought. I'm actually running a home made gasket right now without any problems - dont know why you have problems?

[TA-022]

oil resistant gasket paper is what ive used in the past.
cut the outside ... bal-pein hamer tap the gasket onto the fitting and all the holes fall out etc etc.

Still like that 2 yrs to date and no issues.



Witzl ... pcv issue is as far as i know if the pcv jams shut then the crank case would pressurise and blow the 1st weakest gasket it gets to.

I had a straight hose to a catch can at 1 stage where somehow the feed line kinked.
Buldged the gasket in two spots. 1 being at the rear of the head which explained the oil poured down along the bellhousing

i always thought this was the pcv

[tricky]

TA-022, I thought that was a PCV too... There could be one integrated into the valve cover, but I thought that was just baffling so that oil wasn't flung off the cams straight into the ventilation system, but I've never actually checked. I guess I could suck and blow on it to check... That would be met with the delight of onlookers!

By in front of the throttle do you mean it is on the open air side of the throttle, or spatially, in that picture, it is in front of the observer, so on the plenum side? I've drawn a diagram, but this uni computer is pooing every time I try to login to my image host, so I'll use the power of words...

As I see it, at closed throttle, when there is vacuum in the plenum, the intake is sucking on the crank case. If there was a gasket leak or excessive blowby, there'd be high idle, because that's unthrottled air going straight into the plenum. Is that the way it's set up, or am I misunderstanding?

[The Witzl]

There are two fittings onto the plenum...

# one goes directly into the plenum (unthrottled air).... this is connected to the crankcase vent thru a one-way valve.

# the other is routed to IN FRONT of the throttle (despite looking like it goes directly into the plenum), making it throttled air..... this is connected to the cam cover vent.



The thing you are circling above is actually the anti-dieseling valve - for carbies only. This opens up when you kill the motor to prevent "run-on", also known as dieseling.

[tricky]

Yep, that's what I thought. So you have a degree of circulation when there is a pressure differential on either side of the throttle. I'd be interested to see how reliable this set up is in the long term, because it is probably the best case scenario for an engine not running a scavenger pump.

Witzl, cheers for the info on the anti dieseling valve- All the diagrams I'd seen of that have referred to it as the PCV valve (non toyota diagrams of course), although I notice the pictures of stock 18RGEU's dont have one... Another piece of popular misinformation resolved!

[timbosaurus]

*pointless resubscription to thread*

following a link on CCC website, led me to a company that was apparently doing TRD 18RG parts.

I asked them what parts they stocked and the response was

"We'll start KAMEARI products sales in late April in the U.S., but in the meantime we can process international orders. The shipping costs will depend on your exact address (postal code) and the products, and their quantity. We're in the process of designing our web site, and anticipate it's launch in April. Available parts for the 18RG are adjustable campulleys, headgaskets, high compression pistons, carburator intake manifold, and light weight flywheel. Please let us know if you have any questions."

I thought I'd get prices and specs for gaskets and pistons, but they are a little too pricey for me considering they are in USD and not including shipping.

Pricing is as follows:

18RG 2200cc High Compression Piston Kit $682. Available in 92mm and 92.5mm bores.

18RG headgasket 92mm bore.
1.0mm $231
1.2mm $242
1.5mm $252
2.0mm $284
2.5mm $315
3.0mm $336

They did not say what type of pistons they are, or whether they are genuine TRD parts (that might just be a chinese whisper), but for some people, they might be worth considering so I thought i'd put it out there.

Their email is info"at"kameariusa.com, and their website is www.kameariusa.com

[tricky]

Kameari engine works is an engine tuning company in Japan. They do a lot of 2TG parts, and a few for the 18RG, as well as lots of old nissan crap. They aren't TRD (because they're Kameari, duh), but they're stuff seems good. I designed some adjustable cam gears for the 18RG last year as part of an assignment, and came across the kameari products during lit review, which are the best on the market by far. They don't seem to have a locator to the cam though (ie, they're held only by the central bolt, no pin), which could be a downfall, and I think from memory they were about $200 a gear

EDIT: They have a catalogue online, but it's in japanese and hosted through another supplier. I'll post the link to the catalogue. EDITEDEDIT: They now seem to have a dedicated website in japanese.

[leso]

Have a question regarding the numbers on my camshafts,i have the number 1-351-88251 on my cams....they are fitted to a 88253 head...would these be the original cams...???

thanks 4 all that reply...cheers leso

[Steve M]

Leso, yes, judging by the second segment of the part number you gave, they are the original camshafts.

Here's what I've found so far. Add in anything that I've missed.

88210 head 88210 cams three bolt
88
88250 head 88231 cams three bolt (may have been retrofitted, may not have been)
88250 head 8850 cams single bolt adj.
88253 head 88251 cams single bolt adj.
88270 head 88270 cams single bolt adj.

[Ren_RG28]

Interesting discovery...

Some of you may recall me complaining about a whistling or ringing noise coming from my 18RG when it hit about 5,500. As time went on, the noise came in earlier in the rev range until recently it was coming on as early as 4,000!

It scared the crap out of me and of course I suspected the worst (something internal) so I didn't rev it past 5,500 even when I raced it at Willowbank and ran a 16.9 @ 83mph. A few days after I decided to take it to my mechanic and get him to replace the head gasket (which happened to be blown), and while the head was off he sent it away to get the valves repaired and a port/polish job.

Got it back.. still had the stupid whisle! Now I was completely stumped as to what was causing the problem and just gave up looking... until the other day I was cruising to the local shops and all of a sudden the car started missing HORRIBLY when putting the foot down past 1/4 thottle. Pulled over and checked all the leads and they were in firmly, but it only got worse so I drove the sick little car home.

Saw my mechanic a few days later and he (like me), swore it to be an electrical crossfire of somekind. He checked all the leads, dizzy, replaced the dizzy cap, checked the plugs and timing, until he decided to pull my primary carb to peices. And would you believe the secondary barrel Venturi had come completely loose and was just rattling around in the barrel!

So he fitted the Venturi back in tightly and now there's NO MORE STRANGE WHISTLE! She now revs happily as long as you want without sounding like the engine's gonna blow. So if anyone has a strange whistling noise coming from their 18RG with carbs, check the carbs for loose parts!

Hope this helps someone...