BeNO

I am a bit confused !! I have built couple of engines but nothing like this.

I have a fresh engine. Compression seems to be 60+ PSI on both Rotors. it used to have a hard time to start at the beginning but at least it start when its cold.
The only problem was It almost will never want to start when its hot !!

Now it will never start Cold At All.

I have a microtech LT8s.
Changed C.A.S.
coil packs are working perfectly
clean fuel injectors 1000CC primary 1600CC secondary
new Spark plugs
Fresh Fuel (95 Octane)

I am clue less now !!! I'm thinking I might take the engine apart again !! but it make no sense to do that wouldn't it ???

Any Thought guys ?

Prometheus

iTrader: (2)

60 PSI on all faces???

thats not good...

you built this engine yourself?

you should be seeing high 90's or even 100+ PSI on all faces to be thought of as "fressh"

theo481

iTrader: (10)

I though that depended on the type of gauge you were using...

arghx

iTrader: (3)

it won't start if you give it a little gas? How do you know it's not a tuning issue?

oo7arkman

iTrader: (2)

Does the car even try to turn over? Are the plugs covered in fuel? What kind of porting is done? Have you checked the battery? Have you adjusted the throttle body/TPS?

BeNO

Yes I build it myself.
Some times it sound like its going to start if i step on the throttle. and if i add more fuel to it, the exhaust start to have smoke. but no start !!
Tunning is same as before. even i tried to play with it a little but still no use.
plugs are having a little fuel but no combustion.
Large Street ports. battery are OK 11 to 10.2 on start. TPS is adjusted.

GoodfellaFD3S

iTrader: (213)

Get the battery completely charged and use a jumper pack (or cables with another car) when trying to start the car. You'll be repeatedly cranking it, which can kill the battery quickly.

Get some ATF and pour a couple of ounces into each rotor either via the spark plug holes are the small nipples on the UIM above the turbos. This will help build compression.

Also, if you had the fuel injectors cleaned it's possible they're now gummed up. We always apply voltage to the injectors before installation to make sure they click nicely. Yours may be stuck closed, I've seen it happen more than once.

Do you have a power fc? if so check the voltage across all sensors, paying special attention to the TPS (VTA1 and VTA2).

mx855

I made the mistake of not greasing the injectors when I reinstalled them into the rail and they leaked a little... pull the rails off the car and bridge the F/P connector to ground in the diagnostics box to make sure fuel isn't leaking out the bottom of any of them.

make sure you also clean out the trailing plug holes if you think its flooded, guys use to tell me you only need to do leading, but i could only get it to start on new plugs or cleaning the crap out of all 4, my car use to flood once a week really bad. Once I turned down the water temp fuel correction it solved all the issues.

Heating the plugs with a blowtorch before you put them back in also helps a bit... but as GoodfellaFD3S said.. make sure you get some ATF in there if you can and it will help it.

BeNO

Ok, This is what I did Today.
I put some ATF into the UIM holes and it cranked WAAAY quicker than before !! offcourse it smoked then after 5-10 min. it was fine. the engine responded Smoothly.

let it running for a little over an hour. sounds good, fuel is great, TPS is perfect, absolutely no problem. BUT when i shut it off; i couldn't get it to run again. voltage was low around mid to low 9Volts.

My next thought is to take a compression test tomorrow and check if the compression has got built up !?!?!?!?

Oo and by the way I have a Microtech LT8X

what do you guys think it could be ???

I am eliminating the thought that I have to re-do the engine again :S

GoodfellaFD3S

iTrader: (213)

Re-read my post above.... 9 volts is too low. Try and keep the battery fully charged at 12 volts.

mx855

+1 for the battery being to low.

I assume you have mounted the battery in the trunk, depending on what wire you used you might not be getting the super clean voltage needed to start the car, especially to make the big 1000cc primaries pulse nicely...

have you tried measuring the voltage at the injectors when the ignition is in the on position to verify that it matches that is being read at the battery?

BeNO

Yes. the Voltage was low. New Battery is on.
two days ago. I kept the Car Running for two Hrs. revved it a couple of time. maybe went little crazy on the revving. :p

Started it today with out any ATF and it cranked up right away. now my starter have problem. I'll fixed it tomorrow and then I'll take Cold Compression test and then I'll run it for another hr. and Hot test again.

I am hopping to see 90s.
Mr. Steve Kan had told me it should build up some pressure and the Seal should seal better.

will put some numbers later on.

GoodfellaFD3S

iTrader: (213)

We never have problems with new engines firing up at my shop, but we almost always use all new internal hard seals and springs and new or lightly used rotor housings. If you're having this much trouble keeping the car running, I have to ask--- what mileage and condition rotor housings and apex seals did you use in the build?

BeNO

Me neither, never had any problem with new built.
I have ALL New Apex seal,Springs, Solid side seals, etc.
My rotor housing is pretty new. no scratches.

I am using a reusable water seals. but that is not the issue.

BeNO

OK. Just made compression tests.

Cold Rear 75-76 Hot Rear 60-61
Front 74-75 Front 59-60

I guess, I'll re-open the engine again and check/redo everything !!

All Agree ?? Or is there any other way that a compression might go up to 90 :P

djseven

iTrader: (56)

If you replaced the Apex Seals, springs, and side seals you either have extremely warped housings(only seen this once), extremely worn housings(just because there isnt apex seal damage doesnt mean they are good), or you have some serious clearancing issues likely with the side seal but it would have to be drastic.

BeNO

I don't know !! I am thinking that my Atkins solid corner seals are passing !!

I only saying that because i have had put a "bad" ( lite scratches) rotor housing but didn't see 60 PSI !!

or is it true that Solid Corner seal are very hard to start ???

djseven

iTrader: (56)

Ive used there solid corners and gotten 115+psi, that isnt the problem assuming they were installed correctly and not binding. However you have consistent low compression on all faces which tells me it is the housings, apex seals, or side seals.

BeNO

..So any suggestions ??

Also do you have a pic. of how solid corner seal look like installed ?? Just to verify.

djseven

iTrader: (56)

Side with the indention faces out towards the irons, flat side faces towards the inside of the rotor. I have seen the aftermarket corners not fit perfectly without some clearancing but it is few and far between if the rotors are in good shape.

My suggestion is to pull apart the engine and post pics of the housings here on the forum.

BeNO

... Yeah,, I was hopping someone doesn't tell me to open it. even through I know :P

It gonna take me some time. I am feed up !!

BeNO

Today November 15th, 2010 I have my engine ready for disassemble. I have some issue where my workshop is not being as usual but will continue with the progress.

Hopefully with in the next 24hrs will have some pictures lauded.

BeNO

ok, these are the pictures;

finding are,

1- the bearing was crushed
( I admit its probable my mistake while assembling )

2- the thicker ring on the front stationary gear is scored

3rd & 4th - front rotor housing (compression and exhaust).

5 - rear rotor housing.

everything else look in good shape !! let me know what you think.

arghx

iTrader: (3)

Didn't you check the end play on the e shaft? If you check the endplay right before you dress the engine you should catch a thrust bearing or other problem with the front stack.



This doesn't look so hot but there have been more ghetto builds done than this

BeNO

arghx; Thank you for your comment. and Yes you are right I should have checked.

And I would like to have more suggestion for this issue than critics.