flathead 6 start, what to do next
Thread Starter
|
Tuned
Joined: Feb 2016
Posts: 359
Likes: 32
From: washington
flathead 6 start, what to do next
Hi all, picked up an old 48 with what I believe is a 226 flathead 6. Been toying with starting it for the last few weekends. Is 6v, decent plugs and wires, has spark, bypassed fuel system, with small tank to the carb. It cranks, hits, backfires back through carb and that's about it.
Went ahead and did a dry compression test, then added 2 tablespoons of MMO and here are the results all plugs removed.
60, 45, 0, 30, 75, 65
after MMO 60, 55,0, 40, 80,70
I believe intake valve on #3 is stuck so left it overnight and currently recharging 6v. I have bumped starter with 12v, having cleaned up all 6v, cranks ok and about the same.
What next, ??????????
Went ahead and did a dry compression test, then added 2 tablespoons of MMO and here are the results all plugs removed.
60, 45, 0, 30, 75, 65
after MMO 60, 55,0, 40, 80,70
I believe intake valve on #3 is stuck so left it overnight and currently recharging 6v. I have bumped starter with 12v, having cleaned up all 6v, cranks ok and about the same.
What next, ??????????
Thread Starter
|
Tuned
Joined: Feb 2016
Posts: 359
Likes: 32
From: washington
I sprayed head bolts with the break free last night preparing for the next step, Im guessing a full rebuild is in my future??? just wanted to exhaust all possibilities prior to surgery.
Senior User
Joined: Dec 2015
Posts: 183
Likes: 0
From: Northeast Oklahoma
Similar story here, 48 226, sat for 10 years behind my shop. Pulled the head and inspected, oiled all valves and made sure they were free. My sons and I replaced the head gasket and got it to fire off and run. After running it a few times we rechecked compression and the cylinders evened out as the rings freed up. We got lucky as there was no rust in the cylinders with open valves during it's 10 year rest. Good luck! 
Believe Nothing
Joined: Jun 2004
Posts: 7,519
Likes: 403
From: W. Central FL.
It is going to be hard to start with those low compression figures. You may get it to spin fast enough to build a bit more compression and start by feeding 12V across the starter directly. This will allow the six volt ignition to have hotter spark as well.
Post Fiend
Joined: Sep 2006
Posts: 14,325
Likes: 14
From: Island Southeast Alaska
Trending Topics
Thread Starter
|
Tuned
Joined: Feb 2016
Posts: 359
Likes: 32
From: washington
gauge cluster is a rats nest, so no oil pressure info. brakes are all but not existent so pulling not advisable. Basically hot wiring to the coil
We did put 12v to the starter, with jumper cables seemed to crank about the same as the 6 v. Cables got worm, 15 feet might be too long to get much bang.
Also a side question, the rotor seems to have a full hour of play? Diff seems fine, its an American rotor, just seems like too much??
We did put 12v to the starter, with jumper cables seemed to crank about the same as the 6 v. Cables got worm, 15 feet might be too long to get much bang.
Also a side question, the rotor seems to have a full hour of play? Diff seems fine, its an American rotor, just seems like too much??
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 6 Best Deals Available on New Fords & Lincolns Right Now
Brett Foote
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level
Verdad Gallardo
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Thread
Thread Starter
Forum
Replies
Last Post
areoseek
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
51
Nov 14, 2013 08:22 PM
48 to 49er
1948 - 1956 F1, F100 & Larger F-Series Trucks
12
Oct 29, 2013 12:23 AM
halaferd
1948 - 1956 F1, F100 & Larger F-Series Trucks
31
Oct 9, 2011 11:50 PM
brain75
1948 - 1956 F1, F100 & Larger F-Series Trucks
41
Oct 3, 2011 09:35 AM
nataneely
1961 - 1966 F-100 & Larger F-Series Trucks
22
Dec 6, 2008 07:59 PM