Reading pistons...

[revkev6]

I have an 8ba with 30 over pistons and small chamber edelbrock heads. I don't remember specifically what it has for pistons but I'm pretty sure they are a stock ford style cast piston. Motor was rebuilt 25 years ago and was well cared for with low miles... I pulled it down this year because the tranny needed some work and I figured now would be a good time to clear up all the leaks and put new gaskets in and run the valves. Well she's clean inside with nice cylinder walls with cross hatch still but... but the pistons look like she's burning oil? Oh she gets 140-152lbs in a compression test

What would you do with it?

[Ken/Alabama]

Did it smoke?

[revkev6]

No... it would run rich on startup and burn real black but then run clean except it smelled a bit like coolant which I attribute to low torque on the headbolts

[JSeery]

It looks like it has been running rich to me. Has a sooty look to it.

[revkev6]

Rich for sure.. but the clean piston edges are indications of oil burning correct? I don't really want to pull this motor apart for another 20 years

[Ronnie]

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Too much fuel.

R

[Ross F-1]

It looks like #6 & #7 are much worse than #5 & #8? i.e., right under the carb? And on the lower side? I'd tend to think that's gas washing.

[revkev6]

It has a offy regular dual on it running two 97s with .043 main jets. Shouldn't be running rich enough to wash the piston tops? Carbs are getting rebuilt as well during this process. I am running the horrible paper helmet filters that seem to choke it out. Want to tune it without them

[Kahuna]

I'm in agreement with the others:
Too much fuel

[Ol' Ron]

What distributor are you usning? The stock one worn't work and if it's an aftermarket unit what is the advance curve look like.

[revkev6]

Ron, it's a mallory dual point that was new when the car was built. I gave it a tune up 10 years or so wit new points condenser and coik. I also got the advance kit and set it up to be all in by around 2k. Forget how much advance though.

[JWL]

It is not easy to read the situation. Most performance experts will tell you the clean portion of the pistons indicates the areas where complete, proper combustion is occurring. Your engine looks like several I have disassembled during dyno testing and I would not do anything except put it back together.

Since the specter of over-rich conditions has been raised the investment in a Air/Fuel ratio meter might help you with tuning decisions. I would also encourage you to look more carefully at the total advance being provided by the Mallory.

[Bored&Stroked]

It is really hard to just look at the tops of pistons and determine how it was/is running. We have no idea how long it was idling, how much under load, etc.. It is similar to reading plugs - you can't put them under full-throttle load condition, then drive home and check them . . . the color at that time means nothing. My best guess is that it appears to be rich, so as JWL said, put some O2 sensor bungs about 24 - 36" back from the exit of the exhaust from the block, make sure you have a tightly sealed exhaust system (no leaks) and put a AFR meter on the car that can display your true AFR under different running conditions. Also, make sure you have the correct amount of total advance - and that it is coming in when it should. I run about 24 - 26 degrees total on my flatheads.

[revkev6]

I know I have carb issues. I'm using the stock model A tank with the 8ba pump and it will gravity feed into the motor if I forget to turn the fuel off. My brother did this once and filled the crankcase! Luckily it was caught the next morning and the oil was changed twice. It's hard starting after it sits for 15 minutes which I suspect is from gas draining into the cylinders. I'm already planning to rebuild the carbs with the Stromberg S jets and a little bit leaner powervalve. Although if I take the air filters off it stumbles badly so it can't be too rich?

JWL if you say the pistons are ok I guess that's good enough for me. I do remember reading something about flat head pistons with this clean edge indicating oil burn.

[Bruce Koukalaka]

Definitely running rich, I'd also say the center cylinders are getting raw fuel to add to the problem, making a complete burn impossible. I'll also bet your oil has a gasoline smell to it.

[JSeery]

Little hard to understand how the fuel is draining into the engine with the gravity feed. The needle valves in the carbs should be blocking any fuel, so my guess is there is something wrong with the carbs. Something is allowing the fuel to drain past the float bowls and that's not normal. Not sure how much fuel will flow with this gravity feed, but it may also be fuel starving on the top end.

[cas3]

if the needle & seat are bad it will gravity fill the bowel to flood stage !

[51 MERC-CT]

Originally Posted by cas3

if the needle & seat are bad it will gravity fill the bowel to flood stage !

Ya', I think my doctor told me that one time

[Ronnie]

Originally Posted by JSeery

Little hard to understand how the fuel is draining into the engine with the gravity feed. The needle valves in the carbs should be blocking any fuel, so my guess is there is something wrong with the carbs. Something is allowing the fuel to drain past the float bowls and that's not normal. Not sure how much fuel will flow with this gravity feed, but it may also be fuel starving on the top end.

Also how does the fuel also get by the valves in the fuel pump??

R

[revkev6]

Originally Posted by Ronnie

Also how does the fuel also get by the valves in the fuel pump??

R

my understanding of they way the fuel pump works is that they are one way valves operated by vacuum diaphram. I've never tried but I would imagine the one way valves could allow slow seepage past them in they direction of flow. if you put an electric pump in line with a mechanical pump wont it push right through if the mechanical is not working??

[JSeery]

Originally Posted by revkev6

my understanding of they way the fuel pump works is that they are one way valves operated by vacuum diaphram. I've never tried but I would imagine the one way valves could allow slow seepage past them in they direction of flow. if you put an electric pump in line with a mechanical pump wont it push right through if the mechanical is not working??

It will if it is set up correctly, there are several Barn members that run that type of setup. Need to be sure the fuel pump is in good condition or you can pump fuel into the crankcase.

[revkev6]

so, we are agreeing that it's rich and most likely fuel washed.

what is the "baseline" setting for a dual 97 setup with very mild cam and 239 +30

these are what I remember from memory.
jets= .043
powervalves= unknown
idle jet setting= 3/4-1 turn out

air filters=small paper elements that I think are really restrictive.

what do you have and recommend?? thinking of switching over to something less restrictive on air filters as well

[john in illinois]

I agree that the paper filters may be restrictive. Many do not think so.
They are listed as 2" tall. After you subtract the two 1/4"rubber ends,they have 1 1/2" high filters. They are 4" accross the ends,but filters are 3 1/2".

I was using 43 jets on my 2 97s. An A/F meter showed still rich. I now have 41s
In them,but have not tried it.

John

[JSeery]

With the A/F meter, check it with the filters on and with them off. That should tell you if they are affecting the A/F ratio.

[revkev6]

Originally Posted by JSeery

With the A/F meter, check it with the filters on and with them off. That should tell you if they are affecting the A/F ratio.

if I take my filters off I can't even drive around the block it's popping and farting so bad

[john in illinois]

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I am not using paper filters. I was not clear. The jet changes are just tuning.

John

[revkev6]

Originally Posted by john in illinois

I am not using paper filters. I was not clear. The jet changes are just tuning.

John

Interesting... what size powervalve? From my understanding 97 powervalves have a big effect on mid rpm and tend to lean out on top end when they fall off and you are only on the main

[JSeery]

Originally Posted by revkev6

if I take my filters off I can't even drive around the block it's popping and farting so bad

LOL, well that might be a hint.

[revkev6]

Originally Posted by JSeery

LOL, well that might be a hint.

yeah... it's not a hint! I plan to rebuild the carbs and tune it up without them. since I will have the carbs all apart to rebuild them I am looking to find out what SHOULD be in there for jets and PV's. I'd rather not have to take it back apart again!

Since I was only running it around the block without the filters I may just have been lean on the idle mixture. it also breaks up when it's cold out. like in the 30's or 40s. never really been that much of an issue with a roadster but I've taken a ride around a few times and it never runs right.

when the motor was built it was put together with copper pennies in the exhaust crossovers. when pulled apart one was missing and the other is corroded enough that it's about to come out.

on a side note... . it was put together with the graphite gaskets and the heads look PERFECT inside. the joys of modern coolant!

which gasket set should I be getting to put this baby back together?? I've been looking around for best gaskets and haven't seen one kit that looked good?? the mains seem to weep a bit so I wanted to replace the rope seals... but since there is zero noise coming from the bottom end and the top end looks so damn clean I'm thinking I should leave the crank in place and clean up the pan and just dealing with any drips that come from the upper rope seal?? the one piece seal conversion won't go on with the crank in place correct???


should I clean up the carbon on the combustion area or leave it as is??

[cas3]

the gasket set i just used from speedway had the black rope seals. they are too small to fit the space in the oil pan and timing cover. i had to fill it with goo and then fit the seal in place with a big socket, wait overnight for it to dry and then trim it off. pain in the rear, and i'm expecting it to leak! i think the white rope seals fit...or used to!

[john in illinois]

Rev,I am using a 67 power valve. One step leaner than stock 65.

John

[revkev6]

Originally Posted by cas3

the gasket set i just used from speedway had the black rope seals. they are too small to fit the space in the oil pan and timing cover. i had to fill it with goo and then fit the seal in place with a big socket, wait overnight for it to dry and then trim it off. pain in the rear, and i'm expecting it to leak! i think the white rope seals fit...or used to!

I've read many people that were very happy with the graphite seals?? everyone has said that "best" brand gaskets were what I should use.. I just want to know what part number and where to get them....

basically it looks like it boils down to "graphtite" or copper head gaskets?? I just took off a set of graphtite looking gaskests...

[Bored&Stroked]

Originally Posted by revkev6

I've read many people that were very happy with the graphite seals?? everyone has said that "best" brand gaskets were what I should use.. I just want to know what part number and where to get them....

basically it looks like it boils down to "graphtite" or copper head gaskets?? I just took off a set of graphtite looking gaskests...

The 'Best Gasket' brand is what you're looking for - they have full-engine gasket sets as well as a host of smaller items/sets. Their standard and BigBore sets can come with either a copper head gasket, or a GraphTite head gasket. Their big-port intake gaskets are what I always use - then I port them further. LOL

http://bestgasket.com/engine_catalog...e=Ford-Mercury

Speedway has created their own 'clone' gasket sets that they show as either 'GraphTite' or 'Graphite' -- they are NOT the same as Best Gasket's stuff - they are a far inferior copy. I went through multiple issues with them and sent them back (as I thought I was ordering Best Gasket stuff) - they refunded my money. When I let their people know about the issues their comment was "we've sold hundreds, nobody complained before" -- I let them know that maybe they didn't know enough to complain, but I do.

Attached is the document that I sent to Speedway - it covers some of my issues. Again - they refunded my money . . . but I still don't like how they're site makes you think it is a Best Gasket GraphTite - when it is not.

Speedway Gasket Set Issues.pdf

[revkev6]

Originally Posted by Bored&Stroked

The 'Best Gasket' brand is what you're looking for - they have full-engine gasket sets as well as a host of smaller items/sets. Their standard and BigBore sets can come with either a copper head gasket, or a GraphTite head gasket. Their big-port intake gaskets are what I always use - then I port them further. LOL

http://bestgasket.com/engine_catalog...e=Ford-Mercury

Speedway has created their own 'clone' gasket sets that they show as either 'GraphTite' or 'Graphite' -- they are NOT the same as Best Gasket's stuff - they are a far inferior copy. I went through multiple issues with them and sent them back (as I thought I was ordering Best Gasket stuff) - they refunded my money. When I let their people know about the issues their comment was "we've sold hundreds, nobody complained before" -- I let them know that maybe they didn't know enough to complain, but I do.

Attached is the document that I sent to Speedway - it covers some of my issues. Again - they refunded my money . . . but I still don't like how they're site makes you think it is a Best Gasket GraphTite - when it is not.

Attachment 306640

my question is... which is better graphite or copper?? the graphite seemed to work fine?? thanks for the heads up on speedway... they were never in the running. i hate their branded anything....

[revkev6]

I found the graphtite version for 108 shipped on amazon... seems like a good deal.