12a Rotary Build

[kangaroosa]

so it took the rota for a drive sounds tough

 

 

but thats just it

 

makes a lot of noise but doesnt really go very hard any one know why ?????

 

 

and now it seems really hard to start and then if i do start it i rev it and then it idles down and then stops all together

 

Time to get the timing done and get the carby tuned. Mine went through emmissions testing with 70rwkw with a heap of fuel taken out of it. It was so flat, infact my 5k went harder. It was lean enough to get emmissions down, but was ok as long as i didnt get stuck into it.

Then after a good tune it came out with 103rwkW.

 

So don't be too dissappointed just yet. It will respond really well to a tune. Has it got good compression anyway?

 

don't go giving it hell just yet. Its most likely running lean in the top end.

[chappo12]

awesome thanks mate i was hoping you would respond

 

i wish i had a good pic off the carby set up for a nikki carb.

 

and is it vaccum why it stops after i rev it

Edited April 1, 2010 by chappo12

[kangaroosa]

awesome thanks mate i was hoping you would respond

 

i wish i had a good pic off the carby set up for a nikki carb.

 

and is it vaccum why it stops after i rev it

 

Have you got the brake vaccuum line bolted onto the manifold? That thing got me once, when i swapped from a nikki to weber.

Are both of the vaccuum advance hoses connected to both the carby and the distributor?

 

If your car is not tuned very well, rotaries have a tendancy to kill spark plugs in a flash. I spent hours trying to get the old girl started on E85. Turns out i fouled the (few hundred km old) plugs during that time. A new set of plugs in and it was perfect.

I know theres alot of opinions on spark plugs on 'AR', but I use NGK BR8EQ and have never had an issue. The B8EGV are ok too but alot more pricey.

[chappo12]

the throats at the back of the carb arnt opening its like there not connected

 

and one got pics of the setup for the carb

[kangaroosa]

I don't have pics, but there should be a vac canister from memory on the drivers side/radiator corner of the carby. Thats the unit for the vac secondaries. Alot of people wire the linkages so they become manual. I just did away with it and whacked a weber on.

 

Have a search on Ausrotary. Theres as many threads on there about how to sort out these carbys, as there is threads on here about how to work a 4K.

[chappo12]

yea i need to link the 2nds to the primary with wire or some thing

 

can't find info on how to do it

 

its driving me crazy.

[twinspinna]

chuck a electroinc dizy thats ben locked ansum new race coils on it and get it a good tune dude. if u want some decent power even get the motor ported.

[kangaroosa]

SCROLL DOWN PAGE 2

 

SECONDARIES NOT OPENING

 

MECHANICAL SECONDARIES

 

MODIFY SECONDARIES TO COME ON EARLIER

 

don't bother upgrading the coils. The stock matt black ones are more than sufficient. Mine still throw a spark from the coil to the strut top if I don't have the leads hooked up.

 

Your running issues are most likely all carby related given what you have said. Try playing around with the idle mix screw and the air bleed screw. These along with the idle screw will most likely solve your issues.

Adjusting the idle: in simple terms, adjust the top (air) screw until the desired idle speed is reached, then turn the bottom (fuel) screw clockwise until the engine hunts (leaning out), then back it off a few turns until it runs smooth.

[chappo12]

ok so now the 2nds are hook up heaps better thanks so much.

 

but when i drive it it bogs down and coughs and splats like it runs out of fuel or something. was doing this before i hooked up the 2nds

 

and it runs hot i don't know why. was also doing this before i hooked up 2nds

[RazzaCaine]

ok so now the 2nds are hook up heaps better thanks so much.

 

but when i drive it it bogs down and coughs and splats like it runs out of fuel or something. was doing this before i hooked up the 2nds

 

and it runs hot i don't know why. was also doing this before i hooked up 2nds

 

rotaries have an annoying tendency to run hot... that said, the 12a in my old rx7 never once ran hot

[kangaroosa]

ok so now the 2nds are hook up heaps better thanks so much.

 

but when i drive it it bogs down and coughs and splats like it runs out of fuel or something. was doing this before i hooked up the 2nds

 

and it runs hot i don't know why. was also doing this before i hooked up 2nds

 

Lean engines run hot. If it chokes up an noses over....kinda making a sucking noise but without the power, then it could very well be leaning out. Have you checked the float levels to make sure the float bowls arent draining?

Have you moved the timing from its initial spot when you purchased the engine. Have a play with that and see if it cures it.

 

The engine is still stock standard and was running previous to you buying it i assume, so its going to be one of the obvious things giving you grief.

 

How hot is hot? Tried a digital thermometer to check the accuracy of your in dash gauge?

 

Mine sits on 90deg driving around the streets. 82-83deg out on the highway doing 100km/h. It quickly races up over 100deg when i give it hell through the windies. I guess its all to do with airflow as it sits steady at idle. The radiator is blocked by the bumper, grill, radiator support upright and the radiator support panel will block a great percentage of it aswell if you havent enlarged the opening.

 

Having said that, your ASI rad should perform alot better than my std 3 row RX7 one.

 

What rad hoses are you running? They aren't bent out of shape or kinking under full load? How old is the thermostat? Replace it with a genuine one if you havent already replaced it. Finally, is the cooling system pressurising? I had a dud radiator cap which was leaking, thus making the cooling system less than desirable.

[chappo12]

must be leaning out kanga

 

 

yea heaps of pressure its hooked up to the ke55 dash gauge so I'm guessing rotarys run hotter then 4k motors yea the timing was reset at the rotary shop yea the motor was running when i pulled it out

[kangaroosa]

I wouldnt be using the standard gauge as a good guide. Get yourself some Stewart Warner gauges if you can afford them. Goodluck.

[chappo12]

so i gave it some more fuel it was better

 

but think the plugs have gone in it

 

what hotter plugs do you run kanga

 

and i guess its common for rotarys to use plugs like you said

 

it feels like atmo that you can rgone but i think ev out 1st most of 2nd and then 3rd its like the load is to big so i increased the fuel screw and now my plugs have gone mind you they were the plugs i got when i pulled it out of the wreck

[kangaroosa]

so i gave it some more fuel it was better

 

but think the plugs have gone in it

 

what hotter plugs do you run kanga

 

and i guess its common for rotarys to use plugs like you said

 

it feels like atmo that you can rgone but i think ev out 1st most of 2nd and then 3rd its like the load is to big so i increased the fuel screw and now my plugs have gone mind you they were the plugs i got when i pulled it out of the wreck

 

I would be throwing new plugs at it for sure. I run an elec ignition so the BR8EQ are said to be the better choice.

I have run B8EGV in the past and fouled a few of them. They are claimed to be suited to points style ignitions anyway. Retailing at about $17 a plug, I wasnt putting up with that for long.

I have also run B9EGV (colder plug) and was no different to the B8EGV.

 

I have never dropped down into the '7' plug range.

 

I would have gone through about 4 sets of plugs since my car has been on the road. Most of which were changed out prior to tuneups and are still fine. I also carry a spare set in the glovebox just incase.

 

Until you can get it on a dyno, you wont get the full potential out of it.