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-   -   88 420sel timing (http://www.peachparts.com/shopforum/tech-help/221285-88-420sel-timing.html)

bobby325 05-04-2008 10:05 PM

88 420sel timing
 
Help Could someone please tell me exactly where these timing marks are on the cam gears that are to line up with the cam bearings?????:confused:

stevebfl 05-04-2008 10:48 PM

Behind the gear is a washer about an eighth of an inch thick the marks are on this washer and are clearly distinghished notches about the width and depth that the washer is thick. The first cam stand has a risen arrow cast into it.

bobby325 05-05-2008 08:03 PM

still needing help
 
I found the cam marks I think I'm close the car will run but runs rough. the hole right bank is not hitting on all 4 the timing mark that I believe is the right one it is a little mark on the cam bearing just below the oil tub is this correct?. I can also crack the injector lines on cylinders 1,2,3,4 one at a time and there is no change. Also I removed the plug wires on cylinders 1,2,3,4 at the same time and it ran the same with all 4 wires off I am sooooo confused at this point any help would be fantastic.:confused:

stevebfl 05-05-2008 08:22 PM

Which bank isn't running, passenger side or drivers side?

bobby325 05-05-2008 09:20 PM

help
 
the passenger side is not running

stevebfl 05-05-2008 09:34 PM

Look for an air leak. Have you checked compression. It would be almost unheard of to bend valves on the right head. Have you had the chain off for any reason. How did the problem start?

bobby325 05-05-2008 11:51 PM

chain, guides,heads and cams are all new. the heads where rebuilt at a machine shop with new cams. I checked for a vacuum leak could not find one. the timing cover was completely removed.

stevebfl 05-06-2008 07:20 AM

Has the car run properly since the engine work?

If it has not your problem is that your cam is timed 360deg out. In other words the crank comes to TDC twice for every revolution of the cam. The marks on the cam can be lined up in two different senarios. One is where both valves are rabbit ears open (that is TDC after compression stroke) and rabbit ears down which is after the exhaust stroke and before the intake.

I have seen this done many times as the washer is notched for both senarios. To state it differently: with the crank on TDC the only way one can tell whether #1 or #6 is firing is to look at the distributor. What you have is both #1 and #6 firing at TDC.

bobby325 05-06-2008 07:38 AM

I have the dist at number one and the crank at TDC and the intake valve on #1 with the mark just below the oil tube is just starting to open. its like the whole pass bank is not timed right or something the cam gears and washers where off the and even possible mix I do not know if there is a difference in the timing washers from left to right bank?

stevebfl 05-06-2008 08:12 AM

TDC, Power, exhaust, intake, compression,TDC power again. That is the order. If you have the intake on number one about to open your are rabbit ears down and 360 degrees off (at the crank, 180 at the cam)!

You need to remove the rocker arms on bank one, put the engine on TDC with the distributor pointing at number one, remove the cam bolt and gear, turn the cam 180 degrees till the other notch is up, reassemble. After you have done this the cam lobes will be rabbit ears up. Both lobes will have been off there valves for 90deg (cam rotation) and the next valve to open will be exhaust in 90 deg.

Because the only difference in these two conditions is when the spark occurs, no damage is done. Just don't try and turn the cam with the rockers in place at TDC.

bobby325 05-06-2008 08:32 AM

so the intake lobe on the #1 cylinder should not be touching the valve at TDC and the dist at the #1 firing position?

stevebfl 05-06-2008 09:47 AM

No, the intake and exhaust lobes should be pointed up relatively. The position is widely refered to as rabbit ears up as the lobes form a "V" shape with the point of the "V" pointed at the cam. It will be upside down to that in the opposite wrong position. To verify your condition look at the number 6 cylinder lobes on the other side. They should be opposite not alike (one "V" up and the other "^" down)

bobby325 05-06-2008 04:59 PM

thanks steve your the best runs great


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