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An update on Fuel economy. The Old Trol achieved 15.94 lt/100km almost fully loaded and towing my small camp trailer. I sat at roughly 95-100kmh in 4th gear, and the engine ran all day long at 2800-3000 rpm. Even with the weeping radiator the temp remained at around the third way up the gauge, so I am happy with the overall performance of this little engine.
Yep, that is pretty unreal, but I believe ya. It is over 6km/L with a heavily loaded troll.Quote:
Originally Posted by mudnut
No doubt it's a pretty damn good fuel economy you've produced above.
May be it has something to do with the excess temperature the engine's running atm?!
In mine, temperature gauge has never gone above half way, and when it does, I have an immediate hissy fit. :) ;)
I'm into the mission of getting the best fuel economy out of mine & tuning it for the best balance between performance & economy.
I'm going to have to stay in touch with you a fair bit. :D
Geez that's good economy , didn't realise you could safely rev them that hard , had ours up to 90 rarely because of the high revs but did note better consumption at around 2800 and 85-90 Kay's .
As a matter of fact it's not long been serviced and is chewing more than that .
The Dyno-guy told me, that the RB30 is designed to rev, rather than lug to produce its power. At 100km in 5th, the revs are a little above 2600rpm. The old 4 pot Magna was pretty close to 2800 to 3 grand at 100. I would've liked to sit at around 90kmh, but I had to reach the city before 1:30, so I didn't get trapped on the Ring road. (It was a parking lot anyway, and the average speed was around 5kmh). On the sand, I have no qualms with sitting on 4000 rpm for the soft stuff. The redline on these things is right up there at 5500 and up.
I run a heavier grade oil than specified, as well. 4th is the strongest gear and towing in 5th isn't recommended. I was cringing at the higher revs, but just relaxed after the first couple of hundred ks and let it do its thing.
Remember, Dom, I have the headers fitted, blocked the preheat (for the warmer months only) and removed the heater grid under the carby. I also only run 31" tyres at 35psi.Quote:
Originally Posted by dom14
Yeah, I'm sure headers help, but I reckon it has lot to do with the good dyno tuneup as well.Quote:
Originally Posted by mudnut
I also think your carby is in tip top condition.
I agree with Dom, it must be really well tuned!
Mine is actually running really nicely now, but at last fill it used about 22 litres per hundred...
Mind you, it has a highish rhino roof rack, something like 2 inches of lift... 32 inch aggressive AT tyres etc, but I still think it could do with a damn good tuneup based on those fuel figures
The carby was rebuilt by the Dyno guy last year. Your roof rack acts like a boat anchor.
how many litres per hundred do you think the roof rack would add? I always figured it would add drag, but I've always thought a litre or two per hundred... Maybe I've always been wrong. Lol, wouldn't be the first time
Its hard to say, there is that and as you've written, running the larger tyres as well, will put a lot of pressure on the drive train. Remember sticking your hand out the window as a kid. There was quit a lot of wind resistance to push against at the 100kph. You are also having to accelerate that little bit harder with the weight of the roof rack, and steel bar bull bar, if you have one.
Did I also mention my camper is based on a small trailer?
Yeah, steel bar, with winch, and long range fuel tank too. Cargo barrier, water tank, fridge and slide etc etc etc, probably not the lightest she's ever been.
I'm still thinking a good dyno tune couldn't hurt though, would love to get the consumption under 20 per hundred again.
I take all of the recovery gear out for normal use as well. It makes a big difference, especially having to turn out onto our road. It gets to be a bit of squeak time with log trucks bowling down the hill at us. I only have the alloy bar with a 10mm steel winch cradle and a cheap Aldi winch..
I've been thinking for a while I should chuck her on a weighbridge just for curiosity's sake. Do you know what yours weighs?
Over 2200 at a guess. It is pretty close to stock.
I reckon I'll weigh mine next week and see, be interesting if nothing else.
A quick bit of info for the thread, I recently changed my fan, power steering and air con belts as the old ones were looking worn. Maybe everyone else with an RB30 already knows this, but just in case, here's what I learned.
The specs / part no. I have been told are 13A0890 belts for both power steering and air con, and for some RB30 fan belts while others are 13A0875. Mine is the 13A0875. I couldn't find out any way of identifying which it is without the old belt, but the 13A0890 was clearly too long when I tried fitting it to my car, it had almost no more adjustment after installation, let alone after it would have relaxed somewhat.
After changing the belts I had a horrible whine coming from the front of the motor. I repeatedly tried changing tension on the belts with no change. Changed the worn air con tensioner pulley bearing, and still no change. After isolating the noise to the fan belt, I suspected the replacement belt may be to blame so I bought another brand of belt and changed it over and... FIXED!
The other belt was the right size but still made a terrible noise. I now have Gates brand V belts on all three and it is quieter than before the belt change.
Yeah, it may have something to do with nylon reinforcement material rubbing on the pulley groove edges. Some belts are better than the others.Quote:
Originally Posted by Patrol'n
I reckon something to do with V belt angle not properly matching the pulley groove angle & causing excess friction.
As you may remember, I upgraded the alternator using a EF Falcon alternator, but the belt was squeaking on and off. Even though I aligned the alternator pulley properly with the crank pulley & the tensioner pulley, it still keep doing that. As in your case, I reckon it's the pulley.
When it squeaks(mostly in winter), I just rub a tiny bit of grease on the side of the belt and the noise goes away. Not sure it's the right thing to do, but it does help. I keep the old spare one(which is still good) just in case it snaps.
How did you go with your carby?Quote:
Originally Posted by Patrol'n
Did you try to tune it yourself or did you take it back to the guy who rebuilt it?
Be wary of using ordinary grease on the rubber belt as it will cause the surface it coats to disintegrate. I now use a food-grade grease to coat the lip inside hoses before fitting them.
Yeah mate. I'v heard that. That's why I keep the other one ready at the back of the vehicle all the time. :)Quote:
Originally Posted by mudnut
BTW, what is food grade grease? Vaseline? Or glycerine?
I have little bottle of vaseline somewhere.
Dunno, just a food grade. Haven't really checked it out.
At this stage I've tuned it myself, as I just haven't had the opportunity to take time off work to go see the fella who rebuilt it. I know what you mean about how dirty it looks, although I saw it when he put it on and it was really nice and clean looking and ran 100% spot on when he installed it.Quote:
Originally Posted by dom14
I think it might still be a little rich, still to have a look at the plug and check in more detail, but it feels about right to drive
Unreal economy mudnut!
Definitely need a tune on yours Patrol'n, FWIW I got around 23L/100km fully loaded, with a kayak on the roof and towing a 1.5T camper trailer (That was running 35's too, back to 33's now but don't think it's made any difference). Oh and I was thrashing it because I'm an impatient turd lol.
I also experienced the opposite side of the coin. I hit a big rainstorm past Port Fairy. Fighting a headwind and dodging sheets of water that fill the truck-made grooves in the road. It went up to 19ltrs/100 because I was up and down on the go pedal.
"food grade" means it can safely be eaten....sort of?!Quote:
Originally Posted by mudnut
It's pretty easy to find out if it's running too rich by simply looking at the spark plug tips for traces of brand new soot.Quote:
Originally Posted by Patrol'n
Lean is bit tricky, but still can be spotted from spark plug tips by looking for whitish sort of residue, etc.
Ideally carbies can't be tuned properly on a bench, it's gota be fitted to the vehicle, as each engine's response can be different due to many factors like wear and tear, exhaust system, coolant system, etc etc.
So, if you take it back to the guy, take the whole vehicle and leave it with him.
It's even a not easy for an experienced guy to tune a carby by ear, so it will be quite a challenge for us mere mortals.
i know your carby is running on petrol, but still should look bit better than what I saw in picture after a not too distant past rebuild.
Perhaps, the kinda trekking you do might have something to do with it.
I occasionally run the "better" hi octane petrol to try and flush out deposits that 91 RON seems to leave in the carby.
Yep, she has seen more mud, red dirt, water crossings, overgrown tracks etc in the past three years than I think she ever had in her first 21 years... Before I started running a filter on the snorkel I was forever cleaning bits of tree, bugs and bees out of the air cleaner too, that and plenty of fill ups at country fuel stations. the outside of the carb needs a damn good clean, but I washed the engine bay and degreased the other day, and everything still looks grubby... Was so clean and shiny when I bought it! I'll hit the carb with some cleaner to see how it comes up, but when I get time I will definitely take the car and see the bloke who rebuilt it and see what he can find.
I run 98 whenever I can, as it does go better, but sometimes 91 is all that's available.
I might have a look at the spark to, since it's definitely still rich, inside the exhaust tip is black so I'll pull the plugs on the weekend and check the dizzy just in case, you never know I guess.
BTW, 91RON has no colour now. Recently they stopped using the "red dye".Quote:
Originally Posted by mudnut
I think a carby cleaner added to fuel is a better approach to clean the carbies of the gunk from petrol.
I'm not sure how high octane petrol help clean the carby though.
If the dizzy vacuum advance diaphragm has gone kaput, it will affect the smooth ignition.Quote:
Originally Posted by Patrol'n
Good stuff thanks mate, I will check that tooQuote:
Originally Posted by dom14
Easy to check the advance. Just pop the vac hose off and listen for the change in revs. If no change, block the carby side of the hose with your finger, the engine will run smoother. That means the diaphragm is split or holed.
Get the engine up to operating temp first I believe?Quote:
Originally Posted by mudnut
Well I dropped past the auto shop yesterday and picked up a new timing light that actually works, unlike my old one, so have had a bit of a tinker.
First of all, I tried taking off the vacuum hose, no change in revs. Blocked the vac advance and no change in the way the engine ran. So now I have my new light, I checked the timing and found it was actually at about 20 degrees advanced, so I adjusted that back to bang on 15 degrees with the vacuum advance hose connected. I then checked the timing with revving to around 2500-3000rpm, the timing moved smoothly up to around 30 degrees or so, just past the last timing mark, and then back to 15 degrees once the revs dropped back.
The engine runs better for sure and also starts more easily with the timing back to 15 degrees.
Based on the above, I figure the vac advance is functioning correctly, does that sound right?
Are you running gas or PULP? I don't have the manual in front of me, is factory timing 5 degrees? Can't remember what I've set mine at haha.
I only ever run 98 octane unless I'm somewhere that only has normal unleaded. (In which case it will ping a bit)... Mine has never been gas converted, I've had 2 cars on gas, 1 converted and 1 factory. The factory one wasn't bad, but the converted one had some issues, plus I run my 147 litre tank and aim to install another 70 odd litre aux tank soon for more range (yeah I know, old petrol 4wd so no range really, LOL), so gas isn't on my list of mods.Quote:
Originally Posted by Throbbinhood
My manual says the factory timing is 5 degrees or so without the vac advance pipe attached, and 15 with it attached, which is what I was referring to with the timing settings above.
FUEL TANK BREATHER
Doh! How silly am I. Have had problems with the fuel tank having a vacuum created as the fuel is used. Put it in the too hard basket for a while. I read recently that a vacuum created in a fuel tank is not a good thing, as it flexes the tank in a way it is not designed for. This can cause it to crack. Got off my lazy bum to have a look at it today and I found that the breather for a '94 is in the fuel cap.
I did the test as set out in the FE section of the workshop manual (EF & EC page 44). It says to check that the operation of the vacuum relief valve, which is in the cap. To test: suck on the cap and there should be a click, or valve noise. It also says that if it is blocked, to replace it
I found that it was blocked, so being a tight wad, just whacked the shop vac on the cap and turned it on.
Amazingly it worked and now the valve acts as it should, and lets air in and none out.
Some rather sad news for my RB30. The small plate, or washer behind the timing sprocket on the crank has stripped out and is eating into the crank. The only fix is a new crank, but probably cheaper to get a whole engine. This is just a mongrel thing that the mechanic who changed out the timing belt has caused about 30,000ks ago. It is such a shame as the motor is running as sweet as.
@mudnutQuote:
Originally Posted by mudnut
Craig, I'm not 100% sure about this, but can you please post a close up picture of that scoring on the crank?
What exactly is the problem with that scoring? Oil seal failure?
If that's the case, you may be able to sleeve it and use it as normal thereafter.
Changing the engine or the crank sounds bit too drastic from my end, but I'm not standing right in front of your engine looking straight at it, so you would know how bad it is, better.
The other things that puzzles me is that how a mechanic get something like that wrong. There are two plates. One goes behind the crank gear and the other in front. They both have keys, and have to go through the key on the crankshaft end and then you can turn them either way, which wouldn't matter afaict. How it ate into the crank is something that puzzles me, unless the mechanic is a totally hopeless fella who chose the wrong trade.Quote:
Originally Posted by mudnut