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Ok she is all buttoned up but runs like dookie!


mantas

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YOu had the fire order correct all along.

 

Dont matter what head you have or the length. Just buy the NGK wire sets and throw theose yellow ones away. NGK NE 64 is the part number.

 

if your loosing a cylinder alwasy ck the valve lash !!!!!! plug wire or spark plug. if those dont fix it you could have a biyt loose in compression due to cracked valve hole in piston. valve seat wedged up ect.....

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YOu had the fire order correct all along.

 

Dont matter what head you have or the length. Just buy the NGK wire sets and throw theose yellow ones away. NGK NE 64 is the part number.

 

if your loosing a cylinder alwasy ck the valve lash !!!!!! plug wire or spark plug. if those dont fix it you could have a biyt loose in compression due to cracked valve hole in piston. valve seat wedged up ect.....

 

Btw, i don't know why i did not mention this earlier, I did a comp test earlier and the results were 150, 155, 150, 145 (+/- 1 to 2psi). The cylinder that does nothing when unplugged is the 150 on the end. I changed the plugs last night and ran her about 30 seconds i'll look at the new plugs to see if there are any sure signs that its running lean or too rich in that cylinder. I know my carb is not tuned but no matter what i do with the idle adjustment it does not run any better. I got some duralast wires from VatoZone yesterday and it did not help much.

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Well i came home for lunch and went to monkey around with the carb a little. When i hold the top flaps open and crank the throttle plate only one jet sprays, the other one does nothing. Is this normal or does the other one only come on during vacuum?

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It's not caused by valve lash. You wouldn't get good compression if the lash was off that much and misfiring it would foul the valve seat when running.

 

Looking at the plugs again is a waste of time. So is idle-mixture which affects all four cylinders. You need to a find a cause that only affects one cylinder.

 

When one cylinder doesn't fire, you get unburned gas going throught. Hence the smell. That's a symptom, not a cause. Black plugs are normal. Greasy black plugs are not.

 

#4 cylinder is not firing. Many potential causes, first of which to check is compression. That's good compression. Now I'd look at the spark plug wire. If you pull #4 wire out of the cap, is the metal terminal end of the wire corroded looking? That's a sure sign of a bad wire.

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It's not caused by valve lash. You wouldn't get good compression if the lash was off that much and misfiring it would foul the valve seat when running.

 

Looking at the plugs again is a waste of time. So is idle-mixture which affects all four cylinders. You need to a find a cause that only affects one cylinder.

 

When one cylinder doesn't fire, you get unburned gas going throught. Hence the smell. That's a symptom, not a cause. Black plugs are normal. Greasy black plugs are not.

 

#4 cylinder is not firing. Many potential causes, first of which to check is compression. That's good compression. Now I'd look at the spark plug wire. If you pull #4 wire out of the cap, is the metal terminal end of the wire corroded looking? That's a sure sign of a bad wire.

 

Dizzy cap wires and plugs are new. They were black but not greasy the second time i pulled the old ones out to put in the new ones, all were black even the #3 was not white anymore. I keep scratching my head wondering what the F is going on. Should be getting a timing light and an RPM gauge this week, that will help me dial in the timing and idle. Now when is the engine at TDC? I looked at the marks on the cam gear and coudldnt figure out how they lined up, i've done this millions of times on other cars but was not sure where these guys needed to line up, i think i had it at TDC based on the cam lobes and valves but wasnt sure. Anyone have a diagram?

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It's not caused by valve lash. You wouldn't get good compression if the lash was off that much

Damn you caught me!

 

I dont think you need to worrk about cam timming that far off but be nice to see when the valve cover is off.

 

TDC is based on Crankshaft reference. then you look to see if the cam sprocket V notch is below the dash on the cam tower plate above it.

 

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It's not caused by valve lash. You wouldn't get good compression if the lash was off that much

Damn you caught me!

 

I dont think you need to worrk about cam timming that far off but be nice to see when the valve cover is off.

 

TDC is based on Crankshaft reference. then you look to see if the cam sprocket V notch is below the dash on the cam tower plate above it.

 

http://vimeo.com/19077890

 

Good video. I will try and see what my timing looks like tonight. I'll also check to make sure my distributor is on correctly. Guy who sold me the engine seemed a bit sketchy, i did see it run fine and the first few start ups it was purring like a kitten so i'm not quite sure why anything would have changed unless some part crapped out.

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Timing won't cause 3 plugs to fire and the fourth not to fire. You need to look for something that cause only one plug to be dead. A missing hose on the intake manifold branch for one cylinder will do it.

 

Well well well. We got a genius, I think....now before i can confirm it i'll have to start her up tomorrow. My brake booster hose might have had a leak. the top of it had a slight crack and the nipple that was in there was probably not seating correctly. So i plugged up that hole and i'll find out tomorrow, but it would make sense why 3/4 were having issues where one was not firing correctly and the other was lean. Also the thing ran fine before i installed a nipple for the booster, and it ran ok afterwards but not for long. Timing seems to be dead on, at 0 on the pulley the V lines up with the mark on the cam but my distributor says its all the way at A on the markings. Here are some photos for you gurus to may be shed some more light on this subject. I didn't take any pics of the busted hose or the nipple since that sparked a fuse and i nearly busted half the shit in the engine bay.

 

8181283013_3413fdc13c.jpg

photo 4(6) by onedolla99cents, on Flickr

 

8181318806_84c262bf45.jpg

photo 3(9) by onedolla99cents, on Flickr

 

8181283135_4a7ca9048d.jpg

photo 3(8) by onedolla99cents, on Flickr

 

And does this bolt hole need to be plugged up? What is that for?

 

8181319226_49fb1e0618.jpg

photo 1(9) by onedolla99cents, on Flickr

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Also, is rtv ok for the carb adaptor plate or do i need a gasket? I can make some gasket out of gasket paper but not sure if that is the correct option. And how involved is the tuning of the card, all ive read says i need to figure out the idle mixture using the screw in the back and then set the idle, assuming my jets are of the correct size. It seems too simple to be true...

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under the dizzy is a 8 mm bolt that you can loosen to readjust the timming plate better is its not maxed out to one side. Then recenter timming again .

Thne to the timming light again to whats its speced for. I do 7BTDC to 12 or 14-15 with dual carbs

 

Im going to try that once i get the timing light, should arrive sometime this week. Until then can i rtv between the webber addapter plate or shoud i use that paper gasket that comes with the kits? I have the same paper gasket laying around and i could just cut a new gasket for it.....

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Yes, RTV is what Nissan uses. Because it's cheap, fast, and done correctly is less likely to leak. But ... RTV makes it too easy to botch up the job.

 

So she's running on all four cylinders now?

 

Not yet, have to go home and put the carb back on to findout. Im 100% positive the nipple i put in was the cause of the problem. But as Eagle_Adam mentioned nissan does use the grey silicone which is better than rtv. I coudnlt get my hands on that so went with rtv. I will report back when i get things buttoned up tonight.

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under the dizzy is a 8 mm bolt that you can loosen to readjust the timming plate better is its not maxed out to one side. Then recenter timming again .

Thne to the timming light again to whats its speced for. I do 7BTDC to 12 or 14-15 with dual carbs

 

What do you mean by recenter timing again after setting the dizzy?

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