built motor startup woes

[esahuque]

sup my friend just half built his motor (ka24de) w/ supertech pistons (8.6 to 1). his setup is as follows:91 ka24de w/ 96 head 91 intake manicxracing t2 bottom mount turbo manigti-r t28 w/14psi wastegate660cc deatschwerks inj.holley adj. fpr w/ fuel pressure gaugecxracing intercooler setupebay bovsupertech 8.6 to 1 low comp pistons on stock rodsz32 mafsemance tuneebay turboback exhaust.

we started it once and it ran ok for about 6 minutes then we turned the car off. we let it sit for a second and started it again, it ran ok then started to bog down so he killed it. after this we can't start the car anymore. we're getting fuel and spark but stupid low compression. we let all the fuel dry out over nite in the cyl. and changed the oil. we then unplugged the plug wires and injectors and cranked on it to try to build compression. we also put a drop of oil into the cylinders. still low compression. any ideas?

[gaehrings13]

Maybe engine timing was off and you bent the valves. Its a possibility. After you guys put the timing did you try gently spinning the motor to make sure there wasn't any interference.

[turbonola]

no we didn't but how could that happen if we had everything set to tdc? head and motor, everything was freshly redone. so i mean what's the deal.

[spank044]

What cams did you use? Also it is very easy to bend valves, I did it when I was adjusting my 248/248 setup. The crank spun fine by hand , but once it started TAP TAP TAP TAP TAP. $245 dollars later I have some new valves and seats. Do a leak down test on each cylinder and see if you hear air going into either manifold.

[kouki_hmongster]

What cams did you use? Also it is very easy to bend valves, I did it when I was adjusting my 248/248 setup. The crank spun fine by hand , but once it started TAP TAP TAP TAP TAP. $245 dollars later I have some new valves and seats. Do a leak down test on each cylinder and see if you hear air going into either manifold.

That is pretty scary. me and my bro picking up his motor this thurs and i was wondering since i got the shop to build the whole motor, then would i have to worry about my cam timing? got Briancrower v2 camshaft+vavle spring and retainer kit+new timing chain kit, how would i know if the timing for the cam is bad? it is stated that these cams should be a direct bolt on.

i dont doubt the guy who's building my motor, but just want to make sure everything is okay. i mean the guy builds race car all day long so i guess it should be fine.

[turbonola]

i'm using stock 96 cams, i'll check the timing. but even if i did **** that head up i have a stock 91 head whose cam caps i just found

[esahuque]

What cams did you use? Also it is very easy to bend valves, I did it when I was adjusting my 248/248 setup. The crank spun fine by hand , but once it started TAP TAP TAP TAP TAP. $245 dollars later I have some new valves and seats. Do a leak down test on each cylinder and see if you hear air going into either manifold.

ouch, maybe i did bend some valves. i did hear a tapping went it started the first 2 times but it wen't away and the motor started to bog. i wouldn't hafta replace pistons also would i cuz if i do i'm gonna raise compression to 9 to 1 lol.

--turbonola--

[esahuque]

[480sx]

Your intake cam is retarded by a tooth or two.

Re time that cam, make it so its pointing at about 110 degrees, at the same angle that the exhaust cam. Hopefully your lower timing chain is in right, or else your still screwed.

[srblacks131]

Why would he still be screwed if the lower chain was off. I wouldnt think that would matter just as long as you line everything up. Your intake cam does look off by a little bit but Ive had mine that far off before and it didnt bend any valves or anything. When you put the pistons in did you put the rings on correctly?? Not upside down or anything??

[turbonola]

i put the rings on according to supertech specs

[turbonola]

i'm gonna redo timing and try it again, probably tomorrow. thanks folks i'll keep ya'll posted on my adventures.

[spank044]

Do a compression test. Sounds like what mine did. Fired up and ran great in low rpm, but the first rev to 8200 and tap tap tap then it sputtered and died. If you have stock pistons then you should be ok. Look for polished marks on the valves and pistons in the carbon. Did it start back firing at all. The only reason I hit was because I was using the DIY JWT adjustable cam gears and the 248 cams to get as much out of the timing as I could but forgot to factor in the timing from the non stock cam on the intake. Here's a couple good links for cam install and timing;

http://jimwolftechnology.com/w...S.PDFh ... /w...E.PDF

[turbonola]

this don't look right

[S13xCrazy]

Why would he still be screwed if the lower chain was off. I wouldnt think that would matter just as long as you line everything up. Your intake cam does look off by a little bit but Ive had mine that far off before and it didnt bend any valves or anything. When you put the pistons in did you put the rings on correctly?? Not upside down or anything??

ohhh but it does matter. It all matters, these things are pretty sensitive. Had the lower chain off from the top chain...tap tap tap....SON OF A BEACH!!!

[1sikS13]

that my friend looks like you did the same thing my car did, you didnt have the cam gear torque down enough and it un screwed the bolt itself and bent my valves to hell

[turbonola]

well it was my cams as you all saw, so i got my hands on some s13 cams and installed them.

[turbonola]

now my setup reads like this:

91 ka24de w/ 96 head w s13 240/248 cams91 intake manicxracing t2 bottom mount turbo manigti-r t28 w/14psi wastegate660cc deatschwerks inj.holley adj. fpr w/ fuel pressure gaugecxracing intercooler setupebay bovsupertech 8.6 to 1 low comp pistons on stock rodsz32 mafsemance tuneebay turboback exhaust.

[turbonola]

this don't look right

so i guess those gears were the tapping i was hearing.

[nelson8708]

^ from the looks of that picture i would say that gear wasn't torqued to spec and the aligning dowel on the cam made that groove.

[WDRacing]

Glad you got everything up and running man...congrats and happy boosting

WD

[turbonola]

i'm happy as a *** w/ a bogful of d**ks. lol seriously though i hope this time around goes better than last time. i was boosted w/ a t25 before and blew a headgasket. i followed some good advice "if it breaks upgrade it."