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Jrappl 11-19-2020 05:47 PM

Miss on newly rebuilt 292
 

Sorry this is so long, just trying to give all the info I can to get a solution.

I’ve got a miss I can’t figure out in a newly rebuilt 292 y-block, auto (aluminum case 2 speed) in a 59 Edsel. I’ve got it idling at about 575 in park and 480 in gear. The spec say idle in gear should be 450 but that’s too low right now. The idle is pretty good except every 3-4 seconds I get a miss. If I increase the engine speed quickly (in park) to about 2000 it goes up smoothly and strong without any problems but if I hold it at 2000 the miss is immediate and more apparent. I’ve run it for a couple hours total so far, including about 60 miles on the road around town. It accelerates strong (for a heavy 1959 2sp Edsel) and will run at 60 mph without problems but fuel usage seems to be very high – don’t know for sure but seems like around 8-10 mpg from gas gauge movement.

Engine was bored .030 over and crank cut 0.10 under by a trusted machine shop. I did the reassembly, I’ve done a few but this was my first y-block so I did use the factory shop manual for reference. I oil primed the engine using a drill. For the first startup I cranked it for about 5 seconds (nothing), waited a few seconds, cranked it again and it started right up (after 50 years!). It has never backfired. It starts and runs just not as good as it should. Oil pressure is running about 50 at idle and up to 80 as engine speed increases. I’m getting top end oil flow on both sides. Oil is running out of the overflow tubes on both rocker shafts.

I installed new main and rod bearings, new cam bearings (with original cam), new pistons, rings, and wrist pin bushings. New timing set (sprockets and chain) and I followed the shop manual for installation and counted pins several times! I did not have the valves machined but did clean and hand lap them and then installed new springs and retainers. Installed new rocker shafts also. The valve guides, rocker arms and push rods were good and reused. New oil pump, water pump, fuel pump. I’ve adjusted the valves using the shop manual and the 15 minute (90 degree) method, no difference.

I rebuilt the original 1959 Ford 2 bbl carb (48s for jets as called for in the shop manual), I also tried an early 70s Autolite 2100 (don’t know jetting) and it’s currently running on a new 2150 knockoff (Chinese) which is supposed to have 49s for jets. Seems to run best on the new carb but the miss is there on all carbs. I have it adjusted for max vacuum at idle and I’m getting 19-19.5”. The needle does jump a little between 19 and 19.5 but doesn’t drop below 19. There are no vacuum leaks that I can find and the high vacuum at idle seems to indicate there aren’t any.

I’m using the original distributor. I cleaned it up, checked for smooth movement and shaft play (none), checked vacuum advance for leaking (none) and installed a new condenser, points, rotor, cap, plug wires and plugs. I replaced the original coil with a 12v internal resistor Standard Motor UC15T and removed the external resistor from the circuit. I’ve tested the coil resistance and it’s within specs. I’ve also tested resistance of each plug wire and again they are in spec. I don’t see any cracks in the wires and no sparks watching it run in the dark.

Timing is set at 8 BTDC with the vacuum advance plugged at idle. The mechanical advance works and adds about 10-12 (could be 15, don’t remember) degrees as I increase speed. With the vacuum advance plugged in it looks like I get an additional 10-15 degrees and it moves smoothly. So with everything connected as I increase engine speed I get a total of about 35 degrees advance. It’s hard to tell exactly because the crank pulley only has marks for TDC, 10 BTDC and 20 BTDC. I did check the pulley for slipping but the pointer is right on TDC when the #1 piston is at the top.

Point dwell is at 28 at an idle but drops a little (22-24) as engine speed increases to about 2000 rpm.

After the last road run I pulled the plugs and did a compression test. Compression is good with 6 cylinders reading about 147 and 2 at 140. I don’t know why unless the rings on those two are taking longer to seat.
The plugs did not look good. They were darker than I thought they should be (too rich I guess) and 3 were wet with fuel. Funny thing is the porcelain tip on the plugs was only dark (carbon) on half the tip, the other half was tan. I’ve never seen that before and I’ve been messing with engines for 45 years!

I’m hoping someone has an idea why I’m getting this miss. Seems like my spark is not hot enough. I’m going to swap the coil for another just to rule out a bad brand new coil but I’m not holding my breath. Could it be the carb? But why would I get the same miss with 3 carbs I have tried?

scicala 11-19-2020 10:13 PM

Re: Miss on newly rebuilt 292
 

Maybe check to make sure you're getting a strong blue spark that can jump a fair distance.
Also, since your dwell changed a little when you increased the RPM, check to make sure there isn't play in the distributor bushings.
Is it possible there could be one of the valves adjusted slightly too tight ?

Just throwing out thoughts as they pop in my head.

Sal

KULTULZ 11-20-2020 02:43 AM

Re: Miss on newly rebuilt 292
 

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Hot Rod Reverend 11-20-2020 07:09 AM

Re: Miss on newly rebuilt 292
 

It is hard to diagnose such things from afar, but you did a great job in outlining all the work you have done and what you are experiencing. My instincts tell me that this is an ignition problem - the above posts are great places to start, but if you are sure your valve timing and valve lash is correct then you should have compression in each cylinder up to snuff. (those readings above sound fine) You are obviously getting fuel. Your spark is way too weak from the spark plug readings you are getting - that's my vote. I will say this - trying to find quality ignition parts these days for points, condenser, etc, is very difficult. I have had friends that have purchased brand new parts such as these only to have them fail within 30 miles of use or just put out a weak spark. While many guys are running pointless ignitions these days, those that are running points look for NOS parts because of the lack of quality control.

Jrappl 11-20-2020 09:32 AM

Re: Miss on newly rebuilt 292
 

Thanks for the replies. I think that the spark is not strong enough and will be focusing on ignition. I've checked valve lash several times and the valves are not too tight.

I did bypass the external resistor but also replaced the coil with one with an internal resistor so the points should see about the same voltage. The old coil tests ok with 1.4ohm resistance on the primary and about 6K on the secondary. New one with internal resistor tests at 3.3ohm primary and about 8K secondary. I will swap the old one back in just to test but it's 61+ years old so I may also try another new one just for kicks.

As far as I can tell the distributor is an original 1959. When I cleaned it I checked for play/slop in the bushings but didn't notice any. Car has 61K miles on it but was sitting for 45 years! That distributor was a real pain to get out of the block!

I purchased all ignition parts from Rock (coil, points, condenser, rotor, cap, plugs). It's all Standard Motor stuff that I have had good luck with in the past but have no idea where it was made. I do see they sell a UNITED MOTOR PRODUCTS CP501 set of points they call "Heavy Duty". Do you think these are better or still crap?

I'm using OE style Autolite #45 copper resistor plugs. I've recleaned them and gapped to .035 - they look new again. I tested all 8 for resistance and shorts and they all test good. I've always had good luck with autolite plugs. I suppose Platinum might last longer but either should work.

Jrappl 11-20-2020 09:52 AM

Re: Miss on newly rebuilt 292
 

Is the Blue Streak stuff any better?

KULTULZ 11-20-2020 09:59 AM

Re: Miss on newly rebuilt 292
 

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Dobie Gillis 11-20-2020 10:11 AM

Re: Miss on newly rebuilt 292
 

Here's the Wikipedia skinny for Standard Motor Products. Note the reference to Chinese imports. It's likely that their parts related to points and condenser ignition systems are made in China. Parts for what are now considered antique cars represent a very small market so, from a business standpoint, it makes sense to manufacture them offshore where labor costs are lower. You could try the Blue Streak line since the quality is (or used to be) better than their normal stuff. On the points sets be sure to lube the distributor cam with the supplied lube (if they still do that), and bend the wick in the direction of cam rotation. Most of the failures of Blue Streak points were because this was not done.

https://en.wikipedia.org/wiki/Standa...20from%20China.

scicala 11-20-2020 10:30 AM

Re: Miss on newly rebuilt 292
 

And something tells me, on Jan. 20, 2021, the influx of Chinese crap parts may increase.

Sal

craig 11-20-2020 11:39 AM

Re: Miss on newly rebuilt 292
 

I'm sure you have checked this, but since Y blocks have an odd firing order is there a chance you have a couple of plug wires turned around?

55blacktie 11-20-2020 11:55 AM

Re: Miss on newly rebuilt 292
 

You will find many "off-shore" parts on new cars, too. Not all are bad, just as not all American-made parts are good. Manufacturers have to use them to remain competitive, and we Americans have grown accustomed to buying too much stuff because it's cheap. Expect to pay considerably more for what you buy, if you want it made in the U.S., by workers who are paid a living wage.

Jrappl 11-20-2020 12:05 PM

Re: Miss on newly rebuilt 292
 

The wires/firing order is correct. I've checked several times including a couple days ago when I tested the resistance of each plug wire.

I'm going to try replacing the coil and plugging the external resistor back in (and I have a new spare if needed). Internet seems split on using internal vs external with many people saying they removed the external and just use the coil that doesn't need a resistor without problems.

My local parts store has the blue streak coil and points in stock!

KULTULZ 11-20-2020 03:05 PM

Re: Miss on newly rebuilt 292
 

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KULTULZ 11-20-2020 03:14 PM

Re: Miss on newly rebuilt 292
 

Quote:

Originally Posted by scicala (Post 1954176)

And something tells me, on Jan. 20, 2021, the influx of Chinese crap parts may increase.

Sal

Something tells me you are right.

The reason(s) manufacturing went off-shore is cost of labor, unions, OSHA, labor laws, EPA, CORPORATE TAXES, Federal and State regulations, etc. There is no price reduction, just greater corporate profit.

Just did the rear drum brakes on a 2005 TAURUS. MAZDA designed brakes, original drums marked with the FORD Casting ID with BOSCH also stamped and I put on a set of CHI-COM brake cylinders.

All will match perfectly with the MOTORCRAFT CHI-COM front rotors and pads I put on a few years back ... :rolleyes:

darrell 11-20-2020 03:57 PM

Re: Miss on newly rebuilt 292
 

i used a coil without the resistor on a 57.lasted about 2 days same with second one.

yblock57 11-20-2020 06:43 PM

Re: Miss on newly rebuilt 292
 

Just spitballing here... I had a similar intermittent miss on the 272 in my ‘56 f100.

Turned out to be two bad plug wires. They all tested fine when Ohmed, but pulling one at a time from the cap at idle revealed 2 that made little difference.

I keep a couple of long plug wires around to help me diagnose that sorta stuff.

If your ignition parts don’t make any difference, I’d at least try pulling each wire off and see if you get the same bog when each cylinder is dropped.

Good luck

wellcraft17 11-21-2020 05:43 AM

Re: Miss on newly rebuilt 292
 

I had a similar issue with a fresh rebuilt 223 ford six many, many years ago. Spent a lot of time going over anything that would cause a miss and the last thing I checked was the new spark plugs I had installed. Pulled all of the plugs out and installed the old plugs and the engine ran perfectly. Bad plug from the factory and I’ve never used that brand of plug again.

rotorwrench 11-21-2020 10:04 AM

Re: Miss on newly rebuilt 292
 

From my past experience, a lot of Standard Motor Parts stuff was made in Mexico. They have also purchased the Echlin brand of parts that had been good quality products for many years. I don't know what that effect will be on the condensers they manufacture now and in the future.

I still use Echlin brand condensers for now since all of mine are still working well for the moment. I had an iregular miss fire problem with a Ford FE 390 distributor back when I still owned a T-Bird of that vintage. It had the transistorized ignition that was failing so I converted it back to a standard breaker point system. It still had a miss ever now and then so I pulled the distributor and found that the top bushing had enough play to allow point breaker gap irregularity. I replaced it with a good unit and the miss went away.

Lower quality condensers are likely the main problem with the early standard breaker systems. I still buy two or three at a time just to get one that will operate reliably. It's a sad state of affairs but it's doubtful it will get better unless a person fabricates their own condenser or finds one from a reliable source.

Reliable spark plugs would be the next item on the list.

54vicky 11-21-2020 10:45 AM

Re: Miss on newly rebuilt 292
 

I agree with rotor and wellcraft try replacing the wet plugs only.new as usual does not mean they are above being crap.if you have the old ones and they worked use them.went through the same thing a couple of times in last decade or so with NEW plugs

Jrappl 11-21-2020 07:23 PM

Re: Miss on newly rebuilt 292
 

The last time this engine ran before the rebuild was in 1970. It was sitting for 50 years so all the old parts are really old!

Only had a few minutes to work on it today but I put the old coil on and added the resistor back in. It starts and runs about the same - still has the miss. I then pulled wires from the distributor one at a time while it was running and each caused the engine to run rougher.

I do have the old plugs but... at least 50 years old... They may work, the old coil does.

Tomorrow I will get a new set of plugs and points and try again. If that doesn't work I have another new set of wires and I'll replace one at a time and see if that makes a difference.


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