Timing chain question, not the normal one

Information on the naturally-aspirated KA24E and KA24DE engines.
BaliLover
Posts: 1070
Joined: Sat Apr 26, 2003 1:50 pm

Post

I did a timing chain in a Ka24DE a while back, and goofed the TDC #1 part. I set the crank to TDC, and pulled the distributor and VC, couldn't find any shiny links on the chain but the dots on the camshafts looked to be about where I thought they needed to be. I install all new gears and chains, but the new crank gear and idler gear didn't have dots on them. I install the upper chain on the camshafts, lining up the silver links with the dots, set the dist. to #1 and reinstall it. THe car won't start.

I messed with the dist. for a while until the car would run, but its now at like 25BTDC and if I put it back to 15 the car idles like crap. The car runs now, but has no power off the line. I later determined that while I piston #1 was at the top of the cylinder, it must not have been the compression stroke.

My question is this; without the timing marks on the chain and camgears, is there anyway to know if cylinder #1 is at TDC on its compression stroke? My plan is to get cylinder #1 at TDC, remove the cams and turn the upper chain until the silver links are in the area to line up with the gears, then reinstall the cams using pictures of a properly timed KA as a guide.


pregmantis
Posts: 153
Joined: Fri Oct 07, 2005 12:11 am

Post

you can tell if its on its compression stroke by watching what the cam lobes are doing during the stroke. #1cyl intake should be closing or both int&exh should be closed. At tdc comp stroke both valves should be closed.

vvaffle
Posts: 497
Joined: Fri Dec 17, 2004 8:29 pm
Car: 1991 240sx base hatch, 2009 WRX

Post

What I have read before, and listened to when I removed me timing chain guides is this: cylinder 1 is at TDC of its compresion stroke when the cam lobes of cylinder 1 are facing opposite directions.

BaliLover
Posts: 1070
Joined: Sat Apr 26, 2003 1:50 pm

Post

Mine ARE facing opposite directions, and were when I removed the chain, but the original dots on the original cam gets weren't at 12 & 2 oclock. I can roll the engine by hand and there is more than one time when the cam lobes are facing outward and its on TDC #1 from what I remember. Only during one of these are the shiny links also lined up with the dots. I must have removed mine when it wasn't that time.

180fan
Posts: 7799
Joined: Sat Dec 14, 2002 12:16 pm
Car: 89 fastback

Post

bought a cheapo timing chain kit did ya? There shouldn't have been a need to replace the sprockets either, you could have used the original sprockets and started counting links. Eyeballing stuff on your timing chain is usually a recipe for crappy idles or catastrophic failure.


Return to “KA24E / KA24DE Forum”