number 1 and 2 cylinder plugs carboned up

Discuss all things Model T related.
Forum rules
If you need help logging in, or have question about how something works, use the Support forum located here Support Forum
Complete set of Forum Rules Forum Rules

Topic author
stevefa1952
Posts: 5
Joined: Wed Nov 16, 2022 3:58 pm
First Name: STEVEN
Last Name: FALCK
* REQUIRED* Type and Year of Model Ts owned: 1917 touring
Location: North Fort Myers, FL
MTFCA Number: 52204
MTFCI Number: 25552

number 1 and 2 cylinder plugs carboned up

Post by stevefa1952 » Tue Feb 07, 2023 5:16 pm

Motor seems to be missing and running rough. Number 1 and 2 plugs are carboned up with a little clean spot on tip of spark plug. Numbers 3 and 4 are super clean.
Is it a timer problem or coils or something else?
no trouble starting the car. Just does not sound correct.
Steve


TXGOAT2
Posts: 6411
Joined: Sun Feb 14, 2021 10:08 pm
First Name: Pat
Last Name: McNallen
* REQUIRED* Type and Year of Model Ts owned: 1926-7 roadster
Location: Graham, Texas
MTFCA Number: 51486
Board Member Since: 2021

Re: number 1 and 2 cylinder plugs carboned up

Post by TXGOAT2 » Tue Feb 07, 2023 5:23 pm

Not an uncommon problem. Several things could cause it, with a leaking manifold gasket being one.

User avatar

MKossor
Posts: 459
Joined: Sun Jan 06, 2019 7:30 pm
First Name: Mike
Last Name: Kossor
* REQUIRED* Type and Year of Model Ts owned: 1927 Touring
Location: Kenilworth, NJ 07033
MTFCI Number: 22706

Re: number 1 and 2 cylinder plugs carboned up

Post by MKossor » Tue Feb 07, 2023 5:25 pm

Optimal engine performance depends on many variables. Start/resolve with the easy ones and address all until the engine performs to your satisfaction.

Clean/gap plugs, Clean/replace timer, clean/replace coil points, properly tune coils for equal and consistent firing Time, run compression or leak down test on all cylinders to check valves for good/uniform compression. Good luck with your troubleshooting and repair.
I-Timer + ECCT Adjusted Coils = Best Model T Engine Performance Possible!
www.modeltitimer.com www.modeltecct.com


Scott_Conger
Posts: 6431
Joined: Sun Jan 06, 2019 11:18 am
First Name: Scott
Last Name: Conger
* REQUIRED* Type and Year of Model Ts owned: '13, '15, '19, '23
Location: Clark, WY
Board Member Since: 2005

Re: number 1 and 2 cylinder plugs carboned up

Post by Scott_Conger » Tue Feb 07, 2023 5:26 pm

leaking manifold is almost always the problem
Scott Conger

Tyranny under the guise of law is still Tyranny

NH Full Flow Float Valves
Obsolete carburetor parts manufactured


Art M
Posts: 843
Joined: Wed Jun 19, 2019 12:57 pm
First Name: Art
Last Name: Mirtes
* REQUIRED* Type and Year of Model Ts owned: 1923 Touring
Location: Huron, Ohio
MTFCA Number: 32489
MTFCI Number: 24068
Board Member Since: 2016

Re: number 1 and 2 cylinder plugs carboned up

Post by Art M » Tue Feb 07, 2023 6:57 pm

I was having trouble with #1 and #2 spark plugs getting very oily. After doing a lot of work that didn't solve the problem, i discovered that I was over filling the engine oil. I thought more is better. Reduced the oil level to just barely at the upper valve. The problem was solved.

Art Mirtes


Norman Kling
Posts: 4072
Joined: Tue Jan 08, 2019 1:39 pm
First Name: Norman
Last Name: Kling
Location: Alpine California

Re: number 1 and 2 cylinder plugs carboned up

Post by Norman Kling » Tue Feb 07, 2023 8:23 pm

If the carbon is oily, you are burning oil, however if it is black you are running rich gas mixture. Since it is on 1 and 2 I would very much suspect that the intake manifold gasket has a leak on 3 and 4. Since they have the same port of the manifold. If it sucks in air at that point, the mixture needle is enriched to compensate for extra air going into 3 and 4. The manifold connection for 1 and 2 is normal, so when the mixture is enriched, those two cylinders run rich. The cure for this problem is new manifold gaskets. The ones with glands and copper rings seal the best if the surfaces of the manifold and block are clean. The exhaust manifold must also be straight so that the ports align with the ports on the block.
Norm


Les Schubert
Posts: 1311
Joined: Thu Jan 10, 2019 5:47 pm
First Name: Les
Last Name: Schubert
* REQUIRED* Type and Year of Model Ts owned: 27 roadster 13 touring
Location: Calgary

Re: number 1 and 2 cylinder plugs carboned up

Post by Les Schubert » Tue Feb 07, 2023 8:29 pm

#4 cylinder runs considerably hotter than #1.
#3 runs hotter than #2. This is the reality of the engine cooling system.

User avatar

Craig Leach
Posts: 1436
Joined: Tue Jan 08, 2019 12:22 am
First Name: craig
Last Name: leach
* REQUIRED* Type and Year of Model Ts owned: 1919 Firetruck/1922 Speedster
Location: Laveen Az
MTFCA Number: 26647

Re: number 1 and 2 cylinder plugs carboned up

Post by Craig Leach » Wed Feb 08, 2023 1:04 am

Hi Steven,
One thing at a time. Start & warm up the engine. Adjust the mixture to to as lean as it will run good, get a fire extinguisher, then spray a
flammable substance on the intake manifold making sure not to let it get close to the carb inlet. If the RPM comes up then it's a good
chance you have a intake manifold leak. If not swap #1 & 2 coils with # 3 & 4 and see if the issue fallows the coils. Try the same with
the plugs. If not look at the timer if you don't find a issue there then it's time for a compression test. Because of the 1-2-4-3 firing order
of a T many things effecting # 1 or #2 or #4 & # 3 will cause a miss in the next cylinder.
Good luck.
Craig.

User avatar

ABoer
Posts: 203
Joined: Mon Jan 07, 2019 2:41 pm
First Name: Anthonie
Last Name: Boer
* REQUIRED* Type and Year of Model Ts owned: 1912 touring 1923 roadster 1925 pickup
Location: Klaaswaal NL
MTFCA Number: 19790

Re: number 1 and 2 cylinder plugs carboned up

Post by ABoer » Wed Feb 08, 2023 7:10 am

The problem with # 1 and # 2 is already in the Book :
The Model T FordOwner by Murray Fahnesstock 1921 .
pag.303-305 .

Toon

Post Reply Previous topicNext topic