No suction on intake stroke

geez..are you the guy that put his hyd' lifters in upside down and could'nt set his rocker clearance's properly?

 

Take your timing cover off and see if you have a chain drive for the cam ( automotive application) or a gear drive (reverse rotation cam).

Do you have it identified as in ind30, or ind31 ind32 ind33 ind???
The odd numbered have a gear and rotate the cam opposite the crank. The even have a chain and rotate the cam same direction of the crank.

You can swap the cam and chain parts.
http://www.sbintl.com/
Might be helpful for parts.

(180* out ??? Really guys )

 

The crankshaft never knows what stroke its on, the cam dictates thats, so 180* out of time can never happen. The only way you can get intake and exhaust switched is with the wrong camshaft, and if it builds the correct amount of compression, cam timing in relation to crank timing is correct.

Swap the cam !

Joe

 

I see why you are into Chevy's

 

It's not possible to install a cam wrong ?

 

Sure it is- but the cam can't be installed wrong if the crank timimg mark is at 12 o'clock. cam timing mark at 6o'clock or 180 different with the timing mark @ 12 o clock. That's the same same and same. As long as crank is at 12.

So the 180 remarks about the cam are irrelevant at best. Hence the appropriate rebuttle to them.

But with crank timing mark at 6 o clock the cam should be at 3 o clock.
In this case the piston went from TDC to BDC.

Now I suppose someone could have installed the cam @ 12 or 6 o'clock with the crank at 6 . That would be 90* different on the cam. He's not describing a TDC/BDC reversal, he's describing a intake/exhaust opening reversal. Tdc/bdc reversal would result in valves crashing into pistons ( not on a flat head) or no compression.


The most likely reason in this industrial engine being questioned is that there isn't a timing chain under the cover but two gears, one on the crank & one on the cam. The cam rotates the opposite direction of the crank.

We will see when he gets the timing cover off.

 

You cannot install a cam 180 out.
Try this. Install a cam and crank with the marks properly aligned. Turn the crank one full turn. Check the marks. The cam will be 180 out. Perfectly normal for any four stroke engine

 

Duh, I was still asleep I guess. 180 would only affect the distributor installation.

 

I will be pulling the timing cover to find out if it is gears or chain, and if the correct cam was installed. I suspect I will come across a gear driven cam and have to replace them with a regular automotive chain and cam. Thanks for all the help, I will keep the post updated with my findings. Thanks

 

Yup some wizards don't have a clue do they. Don't want them working in my shop.

Tig

 

Ah, not exactly. Again, the crank rotates twice (720 degrees) for every time the cam rotates once (360 degrees).
So lign up the marks. Now rotate the crank one turn and look, cam is 180 degrees out. Now rotate the crank one more time, op!, it is back in time. Now rotate the crank one more time, low and behold! it is again 180 degrees out. See the pattern?

 

By Jove, I think he's got it!

LOL! Don't you just love it when that little light goes on and you can see things perfectly clearly?

 

I just worked on a Chrysler flathead six that all the cylinders had low compression. The loose worn timing chain had jumped time. Check compression! Hope this helps.

 

New valves, are they adjusted correctly? They could very well all be off the seats. Run a compression test and then a leak down test. Testing is much easier and a lot less expensive than just tearing stuff apart to look.

 

-----------
If the valves were off their seats,
there wouldn’t be suction on the
exhaust side.

Mart3406
=================

 

Well ? What did you find

 

How did I miss this comedy gold thread? It has both the 180 degree out camshaft on a 4 stroke engine as well as pistons hitting valves on a flathead.

 

You don't have to take the timing cover off. You only need to get a look at the valves, either take the head off or one of the valve covers (on the side of the block, under the manifolds).

If the head is on, there is a pipe plug in the head, above the #6 piston. Take out the pipe plug and you can drop a screwdriver down onto the piston, and see it go up and down as you turn the motor. This was put there for timing the ignition but works just as well for timing the cam. If you have a dial gauge you can measure this very precisely. Or, you can make your own gauge out of a metal or wooden rod if you mark it carefully. If you make your own gauge make sure you put a knob on the end or bend it into a T shape so it cannot fall into the cylinder.

Here is the cam timing spec. This is for a 1949 - 1952 DeSoto or Chrysler six but should be the same as your motor.

Set the valve clearance on #6 intake valve to .014 (this is for checking timing only)(normal clearance .008 intake, .010 exhaust, set hot)

Turn engine until tappet and valve just make contact

Intake opens - 5 to 17 degrees before top dead center (crankshaft degrees)

OR - .011 to .122" of piston travel before TDC.

This can be measured on the #6 piston as described above. #1 and #6 rise and fall together so you can look at #1 valve and measure #6 piston, they are the same.

If your valve opening timing is way off you know the cam was installed wrong or the timing chain is worn out and possibly jumped a tooth.

I would consider the piston method more trustworthy than the timing mark method. Timing marks on an old engine are not always where they are supposed to be for various reasons.

 

Rusty:

Thanks for going directly to the issue and bypassing the drama. Excellent!

 

I'm only sorry I didn't see this sooner. God only knows what inlineNnine has done in the meantime. Hope he checks this thread again before he tears his motor apart.

 

You were here sooner. Post 27

 

Yeah but I can be slow on the uptake sometimes.

 

inlineNmine's profile says last activity on 7-12.

I don't know if logging in to read posts qualifies as activity.

 

Valves won't hit pistons on a flathead no matter what.
Time for a wet and dry comp test.
Engine turns c/w unless it's something really weird.
I once had a starter that turned engine backward. You get suction in the exhaust like that!
Intake becomes exhaust manifold.

 

Agreed. And the newbie chiming in at the end.

Don't he know he's supposed to be bumping old threads?