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-   -   Flooding and Hard starting HELP!! (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/flooding-hard-starting-help-857643/)

turnski 08-15-09 05:38 PM

Flooding and Hard starting HELP!!
 
I currently have a 88 t2 with new rotary performance motor with 2 miles or less on it, It has walbro 255 fuel pump and stock 550 cc injectors and front mounted godspeed intercooler. The motor is street ported and intake is match ported. I've been having a hard time getting this started for the first time and it floods . So what am I doing wrong and what do I need to do to get it running so I can drive it and break it in?

Photonic 08-15-09 06:13 PM

Check compression ASAP A properly rebuilt motor should crank easily if it was lubed properly.

Check spark ?

turnski 08-15-09 06:59 PM

Its got compression, I've got spark cause i've had it started, it just seems to flood real easily what do you think is wrong? It cranks easily, and has 30 psi oil pressure at cranking.

HAILERS 08-15-09 07:34 PM

"time getting this started for the first time "
*******************************************
Can you explain that further?

If the starts are difficult when the engine is cold, but ok when fully warmed up, then make sure the water thermo sensor is plugged in and its output reads a half volt at the ECU when the engine is fully hot. Also make sure the ECU is seeing the START signal from the start circuit when the key is HELD to start. No signal to the ECU when the key is HELD to Start means a too lean mixture when the engine is cold. That does not apply to a fully warm engine though.

turnski 08-15-09 07:46 PM

I have to take the plugs out and dry them off and pull the plug on the circut opening relay ( AKA fuel Pump relay under the dash ) the put them back in and it will attempt to start Ive checked all voltage to the ECU all is good there and battery voltage is 12.85 from the optima. I just need to cure the flooding problem, then move on to the hot start problem next. cause Once I get it started and it clears out ir runs ok but wont idle . but wont start when it gets warm

joeylyrech 08-15-09 07:52 PM

Okay rebuild motor that floods=low compression,cure install a fuel cut off switch so you can cut fuel during cranking.

turnski 08-15-09 07:53 PM

Yes this motor has almost 0 miles on it since being rebuilt br Rotary Performance, so Since I've dropped the moptor in it's been tough to get started ( Running )

turnski 08-15-09 07:54 PM

I pull the fuel pump relay that effectively kills fuel. but ti is still tough to get started.

joeylyrech 08-15-09 08:00 PM

okay so then get some oil in the chambers to raise compression,install a new set of plugs crank the motor with the fuel pump running(for like 5 seconds) then shut the pump off and keep cranking as soon as the motor fires up turn the pump on.Let the car run for a long period of time before you shut it off.After that it should be easier to start.

turnski 08-15-09 08:02 PM

guess it's time to ax the rotary in favor of an LS1 i'm thinking just too many quirks to deal with

turnski 08-15-09 08:05 PM

Yeah I've tried that route as well . shot 20w 50 into the cylinders to get the thig started and got it running till I had a small fuel leak at the injector so had to pull the upper manifold to solve that and then once agaon no start . let the thing sit for a month then instant flood.

HAILERS 08-15-09 08:06 PM

I'd trust ROTARY PERFORMANCE, so it isn't the engine builder.

Rebuilt engines can be difficult to start for the first couple of hundred miles. I'd make me a fuel cut switch and use it. There's no need to be pulling and cleaning sparkplugs or pouring oil into the rotor housings imho. Then again some engines I rebuilt had no problems in the beginning. Has something to do with end pieces on apex seals seperating sooner or later. Just a Guess. Got me.

My bad. Pulling the circuit opening relay is the same as a fuel cut switch, but not as easy to use.

I'd still put a meter on pin 3B to see if its getting the start signal when the key is put to Start and check the water thermo sensor input to the ECU on pin 2I once the engine is fully hot. Should be a half volt approx when fully hot.

BAC's generally help during Start because they are held wide open when the key is Held to Start. Adds more air.

Hot starts are usually too much fuel for ?? reasons. Compression etc. Depinning 3B helps on HOT starts because the fuel amount delivered during starting is cut in half or less. The ECU uses the afm instead of the ECU's internal start map when the ECU does not see the start signal on 3B.

Still got the variable resistor? Might see where its position is now so you can return it to that positon, but turn the sucker fully clockwise for more fuel while idling and see if that helps. Remember it has STOPS at each end of its travel and to not crank past the stops.

There's a thread from the TEAM FC3 site on turbo idle problems. Look there or I might find it and post it later. Deals with things like cracks in the TID duct at the turbo etc. Loose clamps on the BAC's air hose. Stuff.

Sorry, not much to say about it that can help. Mabe later if I think of something.

Part of your problem is the Waldo fuel pump and that's just an opinion. But try making the fuel cut switch so you can get some road time on the engine and see if the start problems go south. Like a few hundred Road miles.

http://www.teamfc3s.org/info/articles/idle.html

I've used starter fluid a lot when I used to have problems. IF you can get it to idle is the problem there though. But if you can get it to idle some, then spray a couple of cans aroung the then front, side, under the intake manifold etc.

Also air leaks at the lower injector grommets can be troublesome. Makes for a rotten idle. Spraying under the intake manifold while idling will make that type of leak show up pretty good.

turnski 08-15-09 08:20 PM

I just hate being frustrated , considering I just spent 5K on a fresh 13bt and it doesnt run . you know.

turnski 08-15-09 08:45 PM

I will check all those items you just listed , and guess I'll have to find a way to attach the BAC because it's currently plugged off because I dont have a fitting welded to the piping exiting the turbo on the new front mointed intercooler . that might help

turnski 08-15-09 08:49 PM

unless I can Tee off the blow off valve nipple thats already exhists on the exit piping for the turbo on the intercooler.

Amur_ 08-15-09 09:59 PM

Had a friend with a TII who had the same problem. He'd gone mod crazy under the hood and one result was that the front coil pack was not mounted in its normal spot - it was nearly flopping about loosely (intercooler piping had somewhat displaced it.) We de-flooded it repeatedly and then I went to check on spark. There clearly was spark, but it looked weaker than my NA's. I cut a short length of wire and ran it from the coil to one of the posts by the main fuse panel at the shock tower.

The car fired right up and was fine after that. How's the grounding on your own coils? Maybe this will help you, maybe not. :)


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