The Ford Barn

Brian · 12-16-2016, 02:53 AM

Can anyone advise the piston clearance when using steel pistons? 39 Mercury. Thank you.

JWL · 12-16-2016, 04:52 AM

The clearance requirement with stock stroke is .060 with new rods and .045 with used rods.

51 MERC-CT · 12-16-2016, 05:59 AM

Piston to head? or piston to bore?

JWL · 12-16-2016, 08:36 AM

Good question!!

Kurt in NJ · 12-16-2016, 09:32 AM

In the Ford book the clearance is listed in lbs pull for a feeler gauge, alum piston the same except in plain bores--you didn't say what bores(tin sleeve, or plain)
steel sleeve, steel piston, .003 feeler gauge, 6-10 lbs pull
plain bore, steel piston , .0025 feeler gauge
more for worn piston, and worn bore

different makes of pistons use different clearance, the listed specs are for Ford parts

Kahuna · 12-16-2016, 11:23 AM

Sponsored Links (Register now to hide all advertisements)

Just use .001 per inch. Done

Brian · 12-16-2016, 12:37 PM

Sorry, I was not more specific in my wording....thank you Kurt, you supplied exactly what I was after.

GB SISSON · 01-25-2018, 01:49 PM

Piston at tdc and right side up?

Ronnie · 01-25-2018, 08:53 PM

Quote:

Originally Posted by JWL

Good question!!

Good answer

R

12-16-2016, 02:53 AM	#1
Brian Senior Member Join Date: May 2010 Location: Masterton, New Zealand Posts: 3,834	piston clearance Can anyone advise the piston clearance when using steel pistons? 39 Mercury. Thank you. __________________ Unfortunately, two half wits don't make a whole wit!

12-16-2016, 04:52 AM	#2
JWL Member Emeritus Join Date: May 2010 Location: Fitzgerald, Georgia Posts: 2,204	Re: piston clearance The clearance requirement with stock stroke is .060 with new rods and .045 with used rods.

12-16-2016, 05:59 AM	#3
51 MERC-CT Senior Member Join Date: May 2010 Location: East Hartford, Ct Posts: 5,898	Re: piston clearance Piston to head? or piston to bore? __________________ DON'T RECALL DOING SOMETHING FOR MYSELF BASED ON SOMEONE ELSE'S LIKES OR DISLIKES

12-16-2016, 08:36 AM	#4
JWL Member Emeritus Join Date: May 2010 Location: Fitzgerald, Georgia Posts: 2,204	Re: piston clearance Good question!!

12-16-2016, 09:32 AM	#5
Kurt in NJ Senior Member Join Date: May 2010 Location: on the Littlefield Posts: 6,158	Re: piston clearance In the Ford book the clearance is listed in lbs pull for a feeler gauge, alum piston the same except in plain bores--you didn't say what bores(tin sleeve, or plain) steel sleeve, steel piston, .003 feeler gauge, 6-10 lbs pull plain bore, steel piston , .0025 feeler gauge more for worn piston, and worn bore different makes of pistons use different clearance, the listed specs are for Ford parts

12-16-2016, 11:23 AM	#6
Kahuna Senior Member Join Date: May 2010 Location: NorCal Posts: 2,617	Re: piston clearance Sponsored Links (Register now to hide all advertisements) Just use .001 per inch. Done

12-16-2016, 12:37 PM	#7
Brian Senior Member Join Date: May 2010 Location: Masterton, New Zealand Posts: 3,834	Re: piston clearance Sorry, I was not more specific in my wording....thank you Kurt, you supplied exactly what I was after. __________________ Unfortunately, two half wits don't make a whole wit!

01-25-2018, 01:49 PM	#8
GB SISSON Senior Member Join Date: Jan 2014 Location: Orcas Island Washington Posts: 4,929	Re: piston clearance Piston at tdc and right side up? __________________ Owner/Operator of 'Jailbar Ranch' on the side of Mt. Pickett. Current stable consists of 1946 1/2 ton pickup turned woodie wagon with FH V8, 1947 Tonner Pickup (red) mostly stock with exception of a cummins 6at turbo diesel, 1946 Tonner Pickup (green) with 226 cu in 6 cyl flathead, 1979 Toyota landcruiser wagon, completely encased in 1947 Ford Jailbar sheet metal. Ok, cornbinder rear fenders..... 'Rusty ol' floorboards, hot on their feet' (Alan Jackson)