The Ford Barn

nq50 · 11-29-2015, 05:22 PM

Hi all,
I decided to check my compression. After running the engine for a few minutes these are the results, 58,51,54 and 56. Good?, Bad?, Indifferent?. What do you guys think?

J Franklin · 11-29-2015, 05:39 PM

Indifferent, next time the head comes off lap the valves. If you like spending money pull the engine and give it a complete rebuild. If mine I would drive it until it presented a problem

Chuck Sea/Tac · 11-29-2015, 06:06 PM

How did you check? Plugs out, carb open, 3 compression strokes? What altitude are you?

Patrick L. · 11-29-2015, 06:28 PM

You didn't say much about the engine. Is it run regularly or has it sat for awhile ? Do you try the test both dry and wet ? Are those numbers the highest the gauge registered after about 7 or 8 revolutions ?
If the test was only done dry, then you try it again wet and see if it makes a difference.
But, I'd recommend just driving it. It'll probably run a good long time.

nq50 · 11-29-2015, 07:09 PM

The engine has only been run about an hour in the past year. I started it and ran the engine for about 2 minutes, shut it down, removed the plugs and did the test dry. The readings were taken after about 5 revolutions. Elevation 860 ft., central Massachusetts.

texas webb · 11-29-2015, 07:34 PM

Sponsored Links (Register now to hide all advertisements)

Squirt a little mmo in and do more than 5 revs.

Patrick L. · 11-29-2015, 07:53 PM

Quote:

Originally Posted by nq50

The engine has only been run about an hour in the past year. I started it and ran the engine for about 2 minutes, shut it down, removed the plugs and did the test dry. The readings were taken after about 5 revolutions. Elevation 860 ft., central Massachusetts.

Drive it for awhile. Maybe add a qt of ATF at each fuel up [ add ATF first and then add fuel].

Mike V. Florida · 11-29-2015, 11:43 PM

Like Patrick said, drive it around a bit more before doing the test. It not so much the value of the readings but the reading being within a pound or three of the others.

Big hammer · 11-30-2015, 07:24 AM

Quote:

Originally Posted by Patrick L.

Drive it for awhile. Maybe add a qt of ATF at each fuel up [ add ATF first and then add fuel].

Thought someone posted adding mmo after gas?!% that's all I recall :-(

Pinesdune · 11-30-2015, 08:47 AM

What oil are you running, try a 15-40 diesel motor oil (yes detergent) run a full tank of fresh premium gas though her (over a week so any deposits in the system can wash out), then try your test. Also check the head bolt torque during the week of running. And change the oil back to whatever you prefer to run in it after the week. Just another opinion

Sent from my iPhone using Tapatalk

Patrick L. · 11-30-2015, 10:19 AM

Quote:

Originally Posted by Big hammer

Thought someone posted adding mmo after gas?!% that's all I recall :-(

I think the key is to make sure the additive is completely mixed with the fuel. I find ATF to be a good cheap upper lube.

Mitch//pa · 11-30-2015, 10:25 AM

You fail to mention the history of this engine. Newly rebuilt, older with miles etc.

Fullraceflathead · 11-30-2015, 11:42 AM

I got 65lbs in the first three cylinders and 55lbs in #4 on a cold engine wide open throttle.
My engine is all stock including the head.
Idles smooth.

nq50 · 11-30-2015, 07:43 PM

The engine does not look like a new rebuild. The truck had been sitting in a garage with a 2003 inspection sticker on it. Fall of 2013 it saw day light and had limited use until Fall of 2014 when I purchased it. I plan on putting it on the road next Spring.

Patrick L. · 11-30-2015, 08:20 PM

So if it appears the engine has sat for quite awhile and will now sit till spring, I wouldn't mind seeing quite a bit of ATF poured in the 4 holes and let it work its way thru the rings and the cylinder walls.

nq50 · 11-30-2015, 09:07 PM

What is ATF?.

noboD · 11-30-2015, 09:17 PM

Good grief, drive the car and have fun with it!!

Mitch//pa · 11-30-2015, 09:21 PM

Quote:

Originally Posted by nq50

What is ATF?.

Automatic transmission fluid

Patrick L. · 11-30-2015, 09:25 PM

Quote:

Originally Posted by noboD

Good grief, drive the car and have fun with it!!

I've agreed. But, I thought he just said he was putting it up for the winter. Or, at least, thats what I thought he said.

nq50 · 11-30-2015, 10:17 PM

Yes I am going to put it up for the winter. I also plan on dropping the oil pan to take a look see.

11-29-2015, 05:22 PM	#1
nq50 Member Join Date: Dec 2014 Location: Holden,ma Posts: 33	Compression Test Hi all, I decided to check my compression. After running the engine for a few minutes these are the results, 58,51,54 and 56. Good?, Bad?, Indifferent?. What do you guys think?

11-29-2015, 05:39 PM	#2
J Franklin Senior Member Join Date: May 2010 Location: Oregon Posts: 5,969	Re: Compression Test Indifferent, next time the head comes off lap the valves. If you like spending money pull the engine and give it a complete rebuild. If mine I would drive it until it presented a problem

11-29-2015, 06:06 PM	#3
Chuck Sea/Tac Senior Member Join Date: May 2010 Location: Between Seattle & Tacoma Posts: 2,354	Re: Compression Test How did you check? Plugs out, carb open, 3 compression strokes? What altitude are you?

11-29-2015, 07:09 PM	#5
nq50 Member Join Date: Dec 2014 Location: Holden,ma Posts: 33	Re: Compression Test The engine has only been run about an hour in the past year. I started it and ran the engine for about 2 minutes, shut it down, removed the plugs and did the test dry. The readings were taken after about 5 revolutions. Elevation 860 ft., central Massachusetts.

11-29-2015, 07:34 PM	#6
texas webb Senior Member Join Date: Dec 2010 Location: San Antonio Texas Posts: 636	Re: Compression Test Sponsored Links (Register now to hide all advertisements) Squirt a little mmo in and do more than 5 revs.

11-29-2015, 06:28 PM	#4
Patrick L. Senior Member Join Date: May 2010 Location: Largo Florida Posts: 7,225	Re: Compression Test You didn't say much about the engine. Is it run regularly or has it sat for awhile ? Do you try the test both dry and wet ? Are those numbers the highest the gauge registered after about 7 or 8 revolutions ? If the test was only done dry, then you try it again wet and see if it makes a difference. But, I'd recommend just driving it. It'll probably run a good long time.

11-29-2015, 11:43 PM	#8
Mike V. Florida Senior Member Join Date: May 2010 Location: South Florida Posts: 14,054	Re: Compression Test Like Patrick said, drive it around a bit more before doing the test. It not so much the value of the readings but the reading being within a pound or three of the others. __________________ What's right about America is that although we have a mess of problems, we have great capacity - intellect and resources - to do some thing about them. - Henry Ford II

11-30-2015, 08:47 AM	#10
Pinesdune Senior Member Join Date: Oct 2015 Location: Canada Posts: 414	Re: Compression Test What oil are you running, try a 15-40 diesel motor oil (yes detergent) run a full tank of fresh premium gas though her (over a week so any deposits in the system can wash out), then try your test. Also check the head bolt torque during the week of running. And change the oil back to whatever you prefer to run in it after the week. Just another opinion Sent from my iPhone using Tapatalk

11-30-2015, 10:25 AM	#12
Mitch//pa BANNED Join Date: May 2010 Location: Bucks County, PA Posts: 11,454	Re: Compression Test You fail to mention the history of this engine. Newly rebuilt, older with miles etc.

11-30-2015, 11:42 AM	#13
Fullraceflathead Senior Member Join Date: May 2012 Location: Chillicothe, Missouri Posts: 1,178	Re: Compression Test I got 65lbs in the first three cylinders and 55lbs in #4 on a cold engine wide open throttle. My engine is all stock including the head. Idles smooth. __________________ "If I asked people what they wanted they would have said faster horses." -Henry Ford "Primitive technology is not a design flaw" 1928 Ford Model A Roadster Pickup 1930 Gordon Smith Air Compressor 1941 Willy's Pickup 1960 Thunderbird-For Sale 1964 Buick Riviera 2x4 425 1965 Pontiac GTO, 455 Super Duty 2004 Dodge Ram SRT-10, V-10 Viper 1977 Charger Jet Boat,460 Ford,Jacuzzi Jet Front Engine Nostalgia Dragster,Supercharged 296 "Fullrace Flathead" Ford Engine Build up on DVD ask

11-30-2015, 07:43 PM	#14
nq50 Member Join Date: Dec 2014 Location: Holden,ma Posts: 33	Re: Compression Test The engine does not look like a new rebuild. The truck had been sitting in a garage with a 2003 inspection sticker on it. Fall of 2013 it saw day light and had limited use until Fall of 2014 when I purchased it. I plan on putting it on the road next Spring.

11-30-2015, 08:20 PM	#15
Patrick L. Senior Member Join Date: May 2010 Location: Largo Florida Posts: 7,225	Re: Compression Test So if it appears the engine has sat for quite awhile and will now sit till spring, I wouldn't mind seeing quite a bit of ATF poured in the 4 holes and let it work its way thru the rings and the cylinder walls.

11-30-2015, 09:07 PM	#16
nq50 Member Join Date: Dec 2014 Location: Holden,ma Posts: 33	Re: Compression Test What is ATF?.

11-30-2015, 09:17 PM	#17
noboD Senior Member Join Date: May 2010 Posts: 319	Re: Compression Test Good grief, drive the car and have fun with it!!

11-30-2015, 10:17 PM	#20
nq50 Member Join Date: Dec 2014 Location: Holden,ma Posts: 33	Re: Compression Test Yes I am going to put it up for the winter. I also plan on dropping the oil pan to take a look see.