Compression dissapeared

[datzenmike]

45 ft lb isn't enough by about half. The cam has a dowel so as long as the sprocket is on, it will turn the cam.

[Scrapson]

I definetly put the chain on my knuckles remember very well. it's a nice day in oregon for the first time in awhile so finish the hood paint and fix the poor L20 it should be on the dowel? there isnt a spot on my sprocket for it .

Edited February 3, 2020 by Scrapson

[datzenmike]

This thing...

 

All sprockets have 3 holes for adjustment.

 

[Scrapson]

then yes it went in im just retarded I haven't looked at it in 2 days ive been so dissapointed in myself 

[Scrapson]

I tightened the cam sprocket with all my weight which is 110 pounds give or take it wants to fire so I just gotta charge the battery. This thing is so cold right now I sucked gas through the line to prime the line but it didn’t sputter and die so I gotta adjust the timing a bit I think but I’ll have my grandpa do that. 

[datzenmike]

Camshaft sprocket bolt is 86-116 ft lbs. You do not want it coming loose.

 

So the compression gauge is hooped?

[Scrapson]

Yeah the gauge was bad I gotta go into town to cash my check so I’ll just buy a new one since our local auto parts shop doesn’t do loaners also harbor freight special or princess auto for the Canadians. The timing is quite right yet so I’m going to triple check everything it did backfire through the carb so that’s a step up I guess?

[wayno]

I cannot recall ever doing a compression test on a gas engine in my life, ignorance is bliss I guess, they run or I fix them and then they run, compression ratio has never been on my list of needed tools, I do have a couple of them ones that one holds in the spark plug hole with your hand, I have no idea if they work.

It's quite simple to set these blocks up to run, TDC, 2am/10pm, and 4pm on the distributor, pour a few drops(not a shot glass) of gas down the carb and hit the starter, they start just about every time, little more difficult with dual SUs but they start, it just takes a little longer/more turning over.

 

[banzai510(hainz)]

don't waist you money on a tester.  Unless you saw a hole somewhere your fine.  No compression most time is a tight valve(rockerarm)

[Scrapson]

So just make it run, sounds good enough for me. 

[Stoffregen Motorsports]

Yes, just fix it!

[Scrapson]

New gauge I got 180 in cylinder one cylinder 2 got 210 cylinder 3 got 240 cylinder 4 got 210. I don’t understand I assume it’s valves. Also the I take manifold got flooded with gas again so yay. 

[datzenmike]

240????seems a bit high by 70 or so.

[Scrapson]

Well it’s also decked 12 thousandths over and before that it has 210 with a warped head. The difference in compression that big does worry me a bit so I’ll adjust the valves and try it from there. 

[wayno]

If someone had not said that the compression was a bit high would you have known the difference, maybe that gas you said flooded your intake manifold got into the cylinder while you were doing the test, are the carb butterflies wide open(gas pedal floored) while your doing the compression test?

How is it flooding your intake manifold, if there are no spark plugs in the head it should not be sucking anything into the cylinders, is gas coming out of the vent tubes in the top of the carb when your turning it over, does everything smell like gas?

Seriously, if fuel is dumping into the block and starts squirting out of the spark plug holes all over and then somehow ignites........................................

 

 

 

 

 

[datzenmike]

Valves only hold the compression in or not, they don't adjust the compression. If you said 180 on all I would call that a new rebuilt engine. I've heard of compressions above 200 but the compression ratio was made higher to begin with. 

[banzai510(hainz)]

stop over thinking this.

your compression is fine,told you you didn't need the tester

start the fucking car

[Scrapson]

My other problem is it won’t start it’ll burp like a chain saw does but nothing else. Compression is okay but I’ll try starting it here in the morning when I get ready for school. 

[banzai510(hainz)]

ck the distributor timing and fuel going in the carb.

 

Be honest if you pour a bit of gas in the carn it should fire off if the timing is close.  try turning the dist one way then the other to see if better.

[Scrapson]

I just thought of the distributor while in the shower I guess shower thoughts are good. I think I should just reset it? Since it won’t run but later I can adjust it. I just want my datsun on the road again I have rims waiting for it some thick boys too. 

[demo243]

Make sure your plug wires are correct.

 

And if you dropped the oil pump while doing rebuild make sure the shaft is correct as well.

 

180 degrees off on the shaft will not allow it to fire - might backfire here an there but won't go

[Scrapson]

The pump it was right it was running the headgasket went out so I got the head fixed and put it back off I didn’t touch anything else besides the head and the manifolds. It was running great it had good compression had power and was quick off the line like it was before it broke. 

[Jersey]

“I didn’ttouch anything else besides the head and the manifolds.”

Why would you feel you need to “reset the distributor”? 

[datzenmike]

The distributor position cannot be changed without dropping the oil pump to move the drive spindle.

 

If you unbolt the distributor and remove it, it can only go back in the position it came out and not possible to be 180 out.

 

The ignition timing IS adjustable through a small range by loosening and twisting the distributor.

 

IF the distributor wasn't removed or touched... if it ran properly before it should run properly now and the timing correct.

[Stoffregen Motorsports]

Go back to square one.

 

Watch Hainz' video and check TDC, the distributor drive spindle, the cam timing, valve adjustment and distributor phasing. Once you can check all these off, then the problems are elsewhere.