• Welcome Visitor! Please take a few seconds and Register for our forum. Even if you don't want to post, you can still 'Like' and react to posts.

3.0 valves AGAIN


crf250r6

New Member
Joined
Oct 15, 2009
Messages
41
Reaction score
0
Points
0
Vehicle Year
2006
Make / Model
frod
Engine Size
3.0
Transmission
Automatic
about a year ago i had new valve seats put in my heads, about 3 cylinders were low on compresion, it would start idleing rough and if let idle long enough cylinders would die. i heard it was a comon problem, seeing is how 2 other buddys rangers did it too. i think its within certan years too( mine is 06), but after a year its starting to do it again, orange engine a machine did my heads, they told me they used hardend seats. i want to find out what causes this, is it exahust temp getting too high? i was thinking of punching out 2 of the cats to free it up. i know it gets hot cause it was the exahust valve seats that were bad, and ive had ford replace a exahust manifold once since it warped, and ive had to weld one that cracked, and some of you may say replace the heads but my buddy had ford replace them and they said they updated them with hardened seats and his started doing it again too. just wonderin what everyone thinks of it, i dont want to pull my heads every 10,000 miles.
 


crf250r6

New Member
Joined
Oct 15, 2009
Messages
41
Reaction score
0
Points
0
Vehicle Year
2006
Make / Model
frod
Engine Size
3.0
Transmission
Automatic
i have a magana flow on it, just a weld on muffler, its an auto, and i dont redline it often at all, the shop that did is supposed to be a good shop that has been around for a long time. theirs has to a problem and a way to solve, cause like i said my got new heads from ford and it just did it again, if the cats are bad will that cause it?
 

Rearanger

Active Member
Joined
Feb 4, 2008
Messages
1,429
Reaction score
23
Points
38
Location
Southeast USA
Vehicle Year
2003
Make / Model
Ford
Transmission
Manual
Engine modifications, add-ons?
 

bcost882

New Member
U.S. Military - Active
Joined
Mar 17, 2009
Messages
1,659
Reaction score
5
Points
0
Location
The Queens Country.....
Vehicle Year
2000, 2011
Make / Model
Ford
Engine Size
3.0L, 1.6L
Transmission
Manual
if they fit you could get heads from an older truck even a 98-00 model and try them
 

crf250r6

New Member
Joined
Oct 15, 2009
Messages
41
Reaction score
0
Points
0
Vehicle Year
2006
Make / Model
frod
Engine Size
3.0
Transmission
Automatic
i thought about getting heads from an older truck but i dont know if they will fit, no mods on it besides a k&n intake.
 

rurouni20xx

New Member
Joined
Jan 13, 2009
Messages
1,176
Reaction score
0
Points
0
Location
natchitoches, la
Vehicle Year
1993
Make / Model
Ford
Engine Size
3.0L V6
Transmission
Automatic
ill tell you what the ford place here told my buddy on his 04 when he burned his valves out. the tune on the newer rangers (99 up) is super lean and any exhaust modifications will burn them out. it causes too much exhaust flow and the temperature in the chambers goes into the exhaust ports and cooks them. he had a magnaflow 1 in 2 out and had all cats when he burned them out, then removed all but the ones at the headers, which warped his heads. he slung two rods one thru the oil pan another thru the block at 210k going back and forth to texas for court. hes on a new engine and looking into a programmer to richen the mix and bring the head temperature down. keep in mind richening the mixture will skrew an emissions test, luckily down here in louisiana we dont have emissions except for baton rouge. as for the older heads bolting on, all 3.0 will but they dont have the same chamber design and the tune is wrong for those heads. easier to go from a 94 to a 99 up than downstepping requires retuning to run correctly from what ive been told.
 
Last edited:

crf250r6

New Member
Joined
Oct 15, 2009
Messages
41
Reaction score
0
Points
0
Vehicle Year
2006
Make / Model
frod
Engine Size
3.0
Transmission
Automatic
when my buddys did it his truck was stock, so is it the actuall heads that are the problem or did they make them run to lean.
 

rurouni20xx

New Member
Joined
Jan 13, 2009
Messages
1,176
Reaction score
0
Points
0
Location
natchitoches, la
Vehicle Year
1993
Make / Model
Ford
Engine Size
3.0L V6
Transmission
Automatic
the tune on the engine on his when it was new cooked his valves and the exhuast helped finish them off, shop said it looked like it was done over time. they ruled it back to used o2 sensors not giving the proper signal but they werent worn enuff to throw a cel. they checked the computer and even reflashed it said it had the right tune they just seen it in a few trucks over time. said keep an eye on all 4 o2 sensors and change them around 50k miles to curb it from happening. btw you ride an 06 crf250r? my coworker had one and i used to race yfz450s, im a certified yamaha tech at the local honda/yamaha dealer lol.
 

crf250r6

New Member
Joined
Oct 15, 2009
Messages
41
Reaction score
0
Points
0
Vehicle Year
2006
Make / Model
frod
Engine Size
3.0
Transmission
Automatic
i did have a crf 250 now i have a crf450.
 

crf250r6

New Member
Joined
Oct 15, 2009
Messages
41
Reaction score
0
Points
0
Vehicle Year
2006
Make / Model
frod
Engine Size
3.0
Transmission
Automatic
can the maf cause it to run even more lean?
 

stmitch

March 2011 STOTM Winner
MTOTM Winner
2011 Truck of The Year
Joined
Jan 29, 2010
Messages
2,259
Reaction score
615
Points
113
Location
Central Indiana
Vehicle Year
2000
Make / Model
Ford
Engine Size
3.0
Transmission
Manual
Yes the MAF can cause a lean condition. It seems likley to me that your air intake is causing problems. If it's over oiled, that can cause issues with your MAF. High flow filters by nature allow more particulates into the engine as well, which can cause problems. (I only mention this because it looks like you spend a lot of time in the desert)

I'd go ahead and check the cats too. If one is plugged, it can cause excessive heat buildup, which could crack or warp your manifolds, which can burn the valves.
 

Rearanger

Active Member
Joined
Feb 4, 2008
Messages
1,429
Reaction score
23
Points
38
Location
Southeast USA
Vehicle Year
2003
Make / Model
Ford
Transmission
Manual
How lean would it have to run to burn valve seats while not showing signs of poor running, hard ignition and sending code? Did you inspect the condition of the spark plugs to confirm lean burn?
 

crf250r6

New Member
Joined
Oct 15, 2009
Messages
41
Reaction score
0
Points
0
Vehicle Year
2006
Make / Model
frod
Engine Size
3.0
Transmission
Automatic
i always check the intake tube to make sure nothing goes past and nothing does, i dont know if it is running lean, it does ping some times, is that a sign of it running lean.
 

rurouni20xx

New Member
Joined
Jan 13, 2009
Messages
1,176
Reaction score
0
Points
0
Location
natchitoches, la
Vehicle Year
1993
Make / Model
Ford
Engine Size
3.0L V6
Transmission
Automatic
he has a drop in filter but he can still overoil it and the oil get on the heated wire element of the maf. this will cause it to read less air coming into the engine and lean out, hence the ping. the ping is detonation from lean condition, thats your issue buddy.
 

Rearanger

Active Member
Joined
Feb 4, 2008
Messages
1,429
Reaction score
23
Points
38
Location
Southeast USA
Vehicle Year
2003
Make / Model
Ford
Transmission
Manual
If combustion temps were that high to burn seats why weren't the valves burnt, surely they have less ability to cool?
 

Sponsored Ad


Sponsored Ad

Staff online

Members online

Member & Vendor Upgrades

For a small yearly donation, you can support this forum and receive a 'Supporting Member' banner, or become a 'Supporting Vendor' and promote your products here. Click the banner to find out how.

Truck of The Month


Kirby N.
March Truck of The Month

Recently Featured

Want to see your truck here? Share your photos and details in the forum.

Follow TRS On Instagram

TRS Events

25th Anniversary Sponsors

Check Out The TRS Store


Sponsored Ad


Sponsored Ad

Sponsored Ad


Amazon Deals

Top