Valve Adjustment help needed - Vielen dank!, She's running! Thanks for all the help! Options

[stephenaki]

OK, so I have searched and can't find a thread related to my situation, maybe because people are smarter and more experienced than me. The question is pretty much spelled out in the topic description.

The crank, rods, piston and cylinders are 2.0, the heads are machined 1.7, what measurement do I use for the valve adjustment? 1.7 or 2.0? (IMG:style_emoticons/default/confused24.gif)

I am leaning towards 1.7 but would like to get an educated opinion from the group. Help please, I want to re-do the valve adjustment before I mess with anything else.

[Bartlett 914]

That is a good question. Makes me want to ask why there is a difference between 1.8 and 2.0 adjustment procedure at all.

[Katmanken]

Which is bigger??

The gap is designed to get smaller as the engine heats up.

If the gap is set to the smaller value and it is wrong, the valve train will expand and the valve may be forced open slightly when the engine is hot. (aka burn a valve)

If the gap is set to the higher value and it is wrong, the valvetrain will expand when hot, there will be a little more gap and the valve train will make a little more noise. (not as loud as cold)

I'd try the max gap value. It's more forgiving. Especially if the engine wears in and the valve gap starts closing.

Per the factory change, they may have added the gap due to observations over time that the valve gap was closing slightly more than expected, or the US customers were stretching the miles between adjustments.
Ken

[Gint]

While I understand that completely, I've heard many times over the years that all the 914 motors can have all the valves set to .006. Having said that though, you've just rebuilt this thing right? You might want to go with and initial setting .008 for break in and then monitor where it goes afterwards. I'm not the expert though...

[tat2dphreak]

I've heard many times over the years that all the 914 motors can have all the valves set to .006.

(IMG:style_emoticons/default/agree.gif) I'd like the cap'n or jake to chime in, but I've always heard .006 on all valves, and that's what I've done in the past.

[stephenaki]

Well, until I get a good answer I am not proceeding with anything else. I don't want to have to do it again! So, I'll just wait till the Cap'n or Jake do chime in but sooner the better as it is getting cold here in Germany and I'd rather not ride the bike this winter unless I have too. (IMG:style_emoticons/default/popcorn[1].gif) Speaking of which, I need to go and cover the bike, she's sitting out in the elements since I haven't been able to park her in the garage.

[Cap'n Krusty]

Your 1.7 heads are unlikely to have sodium filled exhaust valves, so the setting is .006" all the way around. You'll need to reset them at 300 miles, then 1500, and every 3000 thereafter. BE SURE you calculate the deck height and combustion chamber volume accurately and adjust the cylinder base shims accordingly or you're gonna have WAAAAAAY too much compression. The Cap'n

[stephenaki]

Your 1.7 heads are unlikely to have sodium filled exhaust valves, so the setting is .006" all the way around. You'll need to reset them at 300 miles, then 1500, and every 3000 thereafter. BE SURE you calculate the deck height and combustion chamber volume accurately and adjust the cylinder base shims accordingly or you're gonna have WAAAAAAY too much compression. The Cap'n

Thanks, I'll adjust the valves then check compression and see where it is at.

[904svo]

Its a 2 ltr, then adjust .006 intake and .008 exhaust if you are using stock
push rods.

[stephenaki]

OK, so, after fiddling around with trying to find TDC, distributor notch not lined up properly and no mark on the impeller fan, I finally got all the valves adjusted.

Unfortunately, she will turn over BUT, won't start! (IMG:style_emoticons/default/headbang.gif)

Now, she started on Saturday, ran rough but started then cut out and I couldn't get her to start again. Maybe I flooded the motor?

Before I elicit help on the starting piece let me make sure I got TDC correct. I did some searching on the PP forum for finding TDC as well. Here is one simple question as I know it is true on my MG motors. There are two times that TDC on #1 are reached; intake stroke and exhaust stroke. Is it possible that I found TDC on the exhaust stroke and therefore adjusted the valves incorrectly?

If, this is not the case with the 914, then, any suggestions on getting her to start? I am thinking ether to get it going and use any fuel that flooded the motor? If I screwed up what I think is TDC then I guess I'll go back to valve adjustment mode tomorrow! I really wish I married a contortionist!! (IMG:style_emoticons/default/blink.gif)

[tradisrad]

It may be a stupid question, but did you put the dizzy cap back on? All wires hooked up? accidentally bump a wire off of the coil? etc...

[r_towle]

First off, think about what the camshaft looks like.
You share a lobe with two valves.

If you remove both valve covers, when a valve on the left side of the motor is fully compressed, the valve on the right side of the motor is then ready for adjustment, its on the back of that same lobe.

Forget TDC...forget what you know.
Just ensure that the valve on the left side is as open as it can be...rock the motor back and forth a little bit and watch that valve.
When you know its fully open, the valve on the other side is fully closed.

For finding the final TDC mark, use a mirror and look for the notch on the fan closest to the rear of the motor..its not easy to find.
Regardless of how the distributor drive gear is installed, or where the notch on the distributor is located, once you find the mark on the fan, you are on TDC for number one.
From there you need to ensure your firing order is correct.
That is 1432 clockwise looking from the top.

For the gap, its 006 and simple.


Rich

[Cap'n Krusty]

Its a 2 ltr, then adjust .006 intake and .008 exhaust if you are using stock
push rods.

Guess you didn't read the question, huh?

The Cap'n

[Cap'n Krusty]

Your 1.7 heads are unlikely to have sodium filled exhaust valves, so the setting is .006" all the way around. You'll need to reset them at 300 miles, then 1500, and every 3000 thereafter. BE SURE you calculate the deck height and combustion chamber volume accurately and adjust the cylinder base shims accordingly or you're gonna have WAAAAAAY too much compression. The Cap'n

Thanks, I'll adjust the valves then check compression and see where it is at.

NOT "the compression", the "compression RATIO". Has to be calculated before the heads go on. If you're using virgin 1.7 heads, it'll be too high. If you're using 1.7 heads that have been flycut, it'll be way too high. If you left out the head gaskets, as some here are inclined to do, it'll be WAAAAAAAAAAAY too high.

As for looking for TDC by using the mark on the distributor, good luck. It's set by the mark on the fan, and if that wasn't done right, nothing will be right. You don't need to do that unless you're using the antiquated, tedious, effort intensive, and downright old fashioned and inaccurate Pelican Parts technique. Using my technique, easily found in the "classic threads" section of this website, I can have a whole valve adjustment job done while you're still looking for your first (of 4) TDC.

The Cap'n

[SirAndy]

distributor notch not lined up properly

Make sure your dizzy is not 180 degrees off. The shaft with the notch will fit flipped but your engine will never run right.

Ask me how i know ...
(IMG:style_emoticons/default/dry.gif) Andy

[stephenaki]

First off, think about what the camshaft looks like.
You share a lobe with two valves.

If you remove both valve covers, when a valve on the left side of the motor is fully compressed, the valve on the right side of the motor is then ready for adjustment, its on the back of that same lobe.

Forget TDC...forget what you know.
Just ensure that the valve on the left side is as open as it can be...rock the motor back and forth a little bit and watch that valve.
When you know its fully open, the valve on the other side is fully closed.

For finding the final TDC mark, use a mirror and look for the notch on the fan closest to the rear of the motor..its not easy to find.
Regardless of how the distributor drive gear is installed, or where the notch on the distributor is located, once you find the mark on the fan, you are on TDC for number one.
From there you need to ensure your firing order is correct.
That is 1432 clockwise looking from the top.

For the gap, its 006 and simple.


Rich

Rich,
OK, so my presumption is correct and I did screw the pooch on this one. So, remember shade tree mechanic here, I get the sucker to TDC (I can feel the notch where you're talking about, didn't need a mirror) adjust the valve screw that is open to .006." Now, rotate the wheel until I hit TDC mark again and adjust the other valve screw. When you say "valve" I am making the assumption you mean the valve screw on the rocker arm as the actual valve will be closed and I should be able to move the rocker arm up and down slightly.

Is my comprehension correct or am I still way out in left field? I assume that this would cause a problem with starting or just with it running crappy?

As for the other questions, yes, the distributor cap was back on and yes, I checked to ensure all connections were solid. As stated earlier, the car actually fired up and ran, roughly, on Saturday. So close yet so far!! (IMG:style_emoticons/default/lol-2.gif)

[stephenaki]

distributor notch not lined up properly

Make sure your dizzy is not 180 degrees off. The shaft with the notch will fit flipped but your engine will never run right.

Ask me how i know ...
(IMG:style_emoticons/default/dry.gif) Andy

Andy,
I read on the PP forum on how to line it up but am a bit leary on what I am doing given the couple of items that could fall into the sump! The notch on my dizzy is oriented left on the drivers side and just about dissects the #1 & 2 spark plugs. I read that is should be facing the drivers left front wheel? I think I noticed a mark that the dizzy rotor pointed to when I had it at what I assumed was TDC. My assumption was the guys at Boxter marked the new location as TDC.

[stephenaki]

Your 1.7 heads are unlikely to have sodium filled exhaust valves, so the setting is .006" all the way around. You'll need to reset them at 300 miles, then 1500, and every 3000 thereafter. BE SURE you calculate the deck height and combustion chamber volume accurately and adjust the cylinder base shims accordingly or you're gonna have WAAAAAAY too much compression. The Cap'n

Thanks, I'll adjust the valves then check compression and see where it is at.

NOT "the compression", the "compression RATIO". Has to be calculated before the heads go on. If you're using virgin 1.7 heads, it'll be too high. If you're using 1.7 heads that have been flycut, it'll be way too high. If you left out the head gaskets, as some here are inclined to do, it'll be WAAAAAAAAAAAY too high.

As for looking for TDC by using the mark on the distributor, good luck. It's set by the mark on the fan, and if that wasn't done right, nothing will be right. You don't need to do that unless you're using the antiquated, tedious, effort intensive, and downright old fashioned and inaccurate Pelican Parts technique. Using my technique, easily found in the "classic threads" section of this website, I can have a whole valve adjustment job done while you're still looking for your first (of 4) TDC.

The Cap'n

Cap'n
Will look into your thread, as far as the heads, no, not virgin 1.7 heads, no I didn't leave out the head gaskets. The pistons are dished, how much of a difference will this make in the ratio? Learning all the time.

[SLITS]

Pull number 1 spark plug ... stick your finger in the spark plug hole ... have someone rotate the engine ... when you start to feel pressure on your finger you are on the compression stroke (both valves closed) and then you can bring the mark up in the notch, assuming you are rotating the engine in the correct direction.

You can also look for the notch in the flywheel and line it up with the split in the case.

[Sleepin]

Pull number 1 spark plug ... stick your finger in the spark plug hole ... have someone rotate the engine ... when you start to feel pressure on your finger you are on the compression stroke (both valves closed) and then you can bring the mark up in the notch, assuming you are rotating the engine in the correct direction.

You can also look for the notch in the flywheel and line it up with the split in the case.

(IMG:style_emoticons/default/agree.gif)

Go buy this book!

(IMG:http://images.barnesandnoble.com/images/13350000/13354057.JPG)

It helped me out when it came to understanding these interesting little engines! (IMG:style_emoticons/default/biggrin.gif)