Engine "Fluttering"?

Engine, ignition, fuel, cooling, exhaust

Moderators: Ranchero50, DuckRyder

User avatar
colnago
100% FORDified!
100% FORDified!
Posts: 1609
Joined: Tue Jun 14, 2011 8:48 pm
Location: Ridgecrest, CA

Engine "Fluttering"?

Postby colnago » Thu Jan 11, 2018 1:00 am

I'm still breaking in my 352 rebuild, but it just started an unexpected noise the other day. The best way to describe it is as a rapid fluttering, more pronounced when warm. Kind of like the baseball card in your bicycle spokes (c'mon, we all did it, trying to sound like a motorcycle), but not hard enough to be a tap. It seems to increase with engine RPM, and more on the driver side than on the passenger.

Looking on the net, a lot of people say a fluttering sound could be an exhaust leak. I checked the nuts from the manifold to the exhaust pipe. They seemed to be snug, but not "gorilla tight." I snugged them up some more, but couldn't tell if anything changed. I haven't checked the heads to exhaust manifold yet.

Another possibility mentioned was bad spark plugs, but these were new with the rebuild. It's kinda doubtful, but possible, I suppose. I did upgrade to Duraspark ignition.

So, do either of these sound likely? Is there anything else I should check?

Joseph
"Sugar", my 1967 Ford F250 2WD Camper Special, 352FE, "T" Intake with 1405 Edelbrock, Duraspark II Ignition, C6 transmission, front disc brake conversion.

User avatar
DuckRyder
Moderator
Moderator
Posts: 3874
Joined: Mon Jul 19, 2004 3:04 pm
Location: Georgia, Atlanta
Contact:

Re: Engine "Fluttering"?

Postby DuckRyder » Thu Jan 11, 2018 7:51 am

Might be worth checking the plugs for tightness...

I assume it is definitely coming from the engine itself and not down stream exhaust like a Y pipe or muffler?
Robert
1972 F100 Ranger XLT (390/C6/Dana 44 Locker)

"An unarmed man can only flee from evil, and evil is not overcome by fleeing from it." -- Jeff Cooper

Ohiotinkerer
Preferred User
Preferred User
Posts: 365
Joined: Wed Nov 09, 2016 5:49 pm
Location: Galion, Ohio

Re: Engine "Fluttering"?

Postby Ohiotinkerer » Thu Jan 11, 2018 6:02 pm

Might be a long shot but it happened to me once - got a new spark plug that wasn't sealing where the ceramic meets the metal base and it made a strange noise........
"Life is a garden - dig it"........... :thup:

1968 F100 Baseline 2wd - Rangoon Red - 360 2bbl - T18 - power steering and manual brakes
1997 Honda CBR 900RR
1977 MonArk 14 ft jon boat with a 1963 Johnson JW-18 3hp outboard

User avatar
Manny
Blue Oval Fanatic
Blue Oval Fanatic
Posts: 908
Joined: Wed Oct 04, 2006 7:15 pm
Location: Georgia, Lake City
Contact:

Re: Engine "Fluttering"?

Postby Manny » Sat Jan 13, 2018 8:40 pm

DuckRyder wrote:Might be worth checking the plugs for tightness...

I assume it is definitely coming from the engine itself and not down stream exhaust like a Y pipe or muffler?



Yep had one dang near blow out of the bronco don't ask how it was loose. :hmm:
Just another Ford fool named Dan.
The Junk that hangs around
67' F-250 highboy Camper special cross breed currently under way
viewtopic.php?f=22&t=86706
1974 Bronco 302 3 speed
1984 bronco 302 c6 35's
1994 F350 7.3 5spd dually.
woods wrote: The rust holes in my truck were a factory install (very rare).

User avatar
colnago
100% FORDified!
100% FORDified!
Posts: 1609
Joined: Tue Jun 14, 2011 8:48 pm
Location: Ridgecrest, CA

Re: Engine "Fluttering"?

Postby colnago » Sun Jan 14, 2018 2:06 am

Well, it wasn't a plug. They were all snug. I didn't have the time to check all of the bolts for the exhaust manifold; hopefully I can do that tomorrow.

Joseph
"Sugar", my 1967 Ford F250 2WD Camper Special, 352FE, "T" Intake with 1405 Edelbrock, Duraspark II Ignition, C6 transmission, front disc brake conversion.

fastEdsel
Preferred User
Preferred User
Posts: 351
Joined: Thu Dec 28, 2006 12:08 am
Location: Alberta, Canada

Re: Engine "Fluttering"?

Postby fastEdsel » Sun Jan 14, 2018 8:50 am

Did you use your previous 2 barrel carb? My guess is that your carb has an internal vacuum leak where only 1/2 your engine gets fuel at certain speeds hence the flutter. Been there, done that. And depending on the age of your carb a new carb kit can usually fix it. :)

Ren
New Member
New Member
Posts: 117
Joined: Thu Oct 15, 2015 3:12 am
Location: Lompoc, Occupied California

Re: Engine "Fluttering"?

Postby Ren » Sun Jan 14, 2018 10:15 pm

Maybe a small piece of something caught in the fan blade or shroud?
And I can't believe you bothered rebuilding a 352.
Surprised you didn't hear a "fluttering" sound when all that money flew out of yer wallet for the rebuild.

Good luck, though. And I do enjoy reading your posts as I often learn something.

User avatar
Manny
Blue Oval Fanatic
Blue Oval Fanatic
Posts: 908
Joined: Wed Oct 04, 2006 7:15 pm
Location: Georgia, Lake City
Contact:

Re: Engine "Fluttering"?

Postby Manny » Sun Jan 14, 2018 11:18 pm

colnago wrote:Well, it wasn't a plug. They were all snug. I didn't have the time to check all of the bolts for the exhaust manifold; hopefully I can do that tomorrow.

Joseph


Hope fully you find something simple!! :thup:
Just another Ford fool named Dan.
The Junk that hangs around
67' F-250 highboy Camper special cross breed currently under way
viewtopic.php?f=22&t=86706
1974 Bronco 302 3 speed
1984 bronco 302 c6 35's
1994 F350 7.3 5spd dually.
woods wrote: The rust holes in my truck were a factory install (very rare).

User avatar
colnago
100% FORDified!
100% FORDified!
Posts: 1609
Joined: Tue Jun 14, 2011 8:48 pm
Location: Ridgecrest, CA

Re: Engine "Fluttering"?

Postby colnago » Tue Jan 16, 2018 10:49 pm

fastEdsel wrote:Did you use your previous 2 barrel carb? My guess is that your carb has an internal vacuum leak where only 1/2 your engine gets fuel at certain speeds hence the flutter. Been there, done that. And depending on the age of your carb a new carb kit can usually fix it. :)


I did use the previous 4BBL Edelbrock carb. I was thinking it needed a rebuild anyway, just cuz the rebuild is nice 'n shiny, and the carb isn't.

Ren wrote:Maybe a small piece of something caught in the fan blade or shroud?
And I can't believe you bothered rebuilding a 352. Surprised you didn't hear a "fluttering" sound when all that money flew out of yer wallet for the rebuild.


Actually, it's bored over 0.030, so it's really a 357! Now I have one on my hip (Smith & Wesson), and one in the driveway (Ford)! I kept it a 352, just to see people's expressions when I say "352;" they want it so hard to be a 351! As far as the money leaving my wallet, that was more of a "whoosh!" My wife and I had a really good policy on that; don't ask me no questions, and I'll tell you no lies. :lol:

Joseph
"Sugar", my 1967 Ford F250 2WD Camper Special, 352FE, "T" Intake with 1405 Edelbrock, Duraspark II Ignition, C6 transmission, front disc brake conversion.


Return to “Engine”

Who is online

Users browsing this forum: No registered users