##Don't be frieghtened .. it's only the Oct. 2012 Banger Meet##

My 15 year old son and I were on a troubleshooting drive yesterday in our the '31 CCPU we have been rebuilding over the past couple of years. The rebuilt engine was finally sounding good, the timing seemed to be on. Then after making a few stops and then beginning to head home, we started to climb a small hill, shifted from 3rd to 2nd over (I have a mitchell overdrive unit in the truck) and about half way up the hill the truck back fired and stopped like it had run out of gas. I quickly checked the gas valve (I have left it closed before), it was open. tried to quickly restart the truck as I shifted to neutral, the engine turned over but would not start. We coasted to the side of the road. When we stopped some troubleshooting began.
- No leaks to be seen (oil, water or gas)
- the fuel pump was running and delivering gas to the weber 32/36 dgv carb
- all the plug wires and coil wire were attached
- nothing looked loose.

I had him press on the starter rod, the engine turned over but would not start.

So , we pushed the truck the 1-1/2 miles back to the house.

Once back in the garage, I did a compression check, the results were 0, 0, 0, 0 or more like 30 then leak down to 0 on all four cylinders.

The engine is a Riley Two Port, inserted, pressurized Model A Ford engine. I took off the valve covers and the rockers went up and down as the engine was rotated by hand.

My first guess is a blown head gasket. But before I lift the almost 100# head off the block I want to ask you for some advice.

Specs: '31 CCPU
Riley Two Port, inserted, pressurized Model A Ford Engine
Petronix distributor
Weber 32/36 DGV carb

Thanks,

Dave

 

Yes, the alignment is really self centering when you consider the width of the bearing surface compared to say a SB Chevy rod.

 

Check your rocker clearance. If for some reason the adjustment has tightened up, the valves would remain open enough to prevent compression.

Also, check your ignition timing and cam timing.

.

 

Didn't we have a guy here some years ago that had valves bent on a re-pop 4-port?

 

Something doesn't sound right, compression test is far different than leakdown testing. However, I just have a hard time believing that all 4 would let go at the same time. It sure sounds like ignition to me, have you tested ignition?

John

 

I often see the inside of engine blocks painted like this what is the reason for this? Ialways understood keep anythin like paint away from your oil in case it flakes and gets into the system your thoughts please?

 

RussTee,

The main reason to paint the inside of the block is to promote more oil return back to the pan. I agree that having paint flake could cause a problem, preparation is the key. Besides, any paint would be stopped in the filter before it could do any damage. You should take a look closely at what the gears in the pumps look like, many I swear were lapped with gravel or hobbed with a hammer.

John

 

Jeez! Now you have to run tubing (usually 1/8) from that fitting to the gauge. Or screw in your sending unit! I'm sorry but I just assumed that anyone posting on here know's a little basic car stuff The plug in the side of the AB engine is above the pan rail on the center of the south side my engine the way it is parked in the shop. Does that help?

 

Sorry Bill, I miss my Chevy banger (it's on the backburner right now), so I jumped at the chance to add something to the thread

 

I guess the older i get the stupider I get. Need to proof rread!

 

Urb stair wrote in his book that on the way home from a race he put some of the AV gas (racing) fuel in his Ford V8 and drove home pulling the race car. Next morning no compression, valves had run dry and stuck open. Possibly just the exhaust don't remember. Squirted some oil in the plug holes and it eventually fired.

 

More info but not closer to solution:

- checked upper RIley valve train and all is moving clearances are
still where the were when I set then a few months ago
- checked timing gear, it rotates as i turn the engine over by hand
- took off the side cover and all of the block valves go up and down.
- it has been up to operarting temp about 10 times over the past few
months, a few drives around the block, this was the first time more
than a mile from the house.
- checked compression again and it is 30# in cylinder 1 and 0# in the
other four.
- before this episode I was seeing about 105# per cylinder compression
- looking through spark plug holes with a flashlight, I can see the pistons
go up and down
- the timing gears were aluminum when the engine was assembled. I
agree that the 7:1 riley is too much for fiber gears
- placed long Qtips down spark plug holes and did not pick up any water
or antifreeze so I believe the water system is still sealing
- the oil is at the same level as before this episode, and i don't see any
water in it
- I am at a real loss as to why I have no compession

Before I pull the Riley head I am going to do some more thinking.

Thanks, Dave

 

Have you done a leak down test Dave?

That should lead to to your source of lost compression without removing anything but the plugs.

Cheers,
Rob

 

Dave,

You may need to check the cam timing, if slipped, it would affect all cylinders.

Try a timing light on the pulley and see if the timing is close when cranking.

John

 

You might just take the head off and find some bent or sticking valves or both........

 

I doubt a head gasket would effect all the cylinders.

 

Have you tried a wet test? I read about the compression tests you have done but are they both dry and wet?

 

Bill

Wet DRY or STP nothing makes a zero number much better

Valves are open when they shouldn't be ....provada

 

Retorque'g is a must periodically with a stock banger & head especially with the sandwhich type gasket.

I don't know about the Riley head, but what type of head gasket did you use? The "sandwhich type" should be retorqued often.

 

<HR style="BACKGROUND-COLOR: #e5e5e5; COLOR: #e5e5e5" SIZE=1> <!-- / icon and title --><!-- message -->
Thank you for the suggestions so far. This morning I jumped in a did the work to take the Riley Two Port head off the engine to see what is happening inside the engine. Well after the head was off and placed on the bench the issue was found. When I assembled the engine I did not follow Charlie Yapp's advice and place fire wires between cylinder 1-1 & 3-4 in the narrow area on the block. I figures I had a good gasket and did not need them. Well what I found was a blow out of the composite gasket between 1-2 & 3-4. This explains the loss of compression in all four cylinders during checking and also during the leakdown test. I would try to pressurize one cylinder only to have it leak out the adjacent cylinder. Oh my.

Now during assembly I will place fire wires into between the cylinders as the head is reinstalled on the block.

I guess climbing the hill a few days ago made the engine work a bit more than sitting in the garage and blewout the gasket.

I have much empathy for Marshall V Daut, during his cross country drive a few years ago in his A400 with a Riley Two Port that blew a gasket on the side of a deserrted road. I was only 1-1/2 miles from home though.

Just when I think I have it all figured out, these Model A's throw me a curve ball.

 

http://www.jalopyjournal.com/forum/showthread.php?t=704473

Within these few months, Im gonna retorque it for about the fourth time, tonght or tomarrow.

 

Video between the hairpins at Prescott.

 

me and my dad drove 800km to get my new banger, a 1931 with custom headers will go in to my 1929 frame with 30 cowl and 23 rear body more pic will comme later







Also got some new axels an mecanikal brakes, going to run them as they are just overhaled also got som other parts ;

 

appears to be a weber intake !

 

its built for stromberg 97 will be adding a holley 94 i have

 

Kjell, looks like a good start.

 

Need some ideas on how to properly time my "A" motor with a "B" distributor. Before everyone says 'put a "B" front cover on it', let me explain...the motor is going in an AR (early '28 A) frame with a pristine front crossmember. I shutter at the thought of hacking up the front motor mount to convert to the standard front motor mount (and "B" front cover).

Any ideas how to pull this off?

 

Love it.

 

Thanks I just wasnt 100% sure but that is what i did just got it all back together and wanted to add a oil gauge (on the dash) before starting it .