The Ford Barn

Pepsi Mechanic · 07-12-2011, 03:25 PM

I rebuilt Our tillotson over a year ago and she has been working great ...
I Had someone else drive her in a parade on the weekend and the engine barely stayed running and was kicking out black smoke ... very rich ... Found out that the person opened the choke control rod CCW a full turn .Not sure why he did that .. I normally run it at a 1/4 turn ...
So I turned it back to normal ( 1/4 turn )and she still runs rich ... I had to turn it all the way in CW to make her run better ... Any idea's as to what is or went wrong ? I need to do a couple of small shows over the next week and she should be OK for that ,but should I plan on rebuilding the carb later next week?
Has anyone tried the new Tillotson that Mac is selling ?--- I would like to have a spare on the shelf

pat in Santa Cruz · 07-12-2011, 03:51 PM

possibly it was seated too hard before it was turned out a full turn and expanded the orifice. Or, there could have been a speck of dirt in there that washed out when it was fully opened, thereafter allowing greater fuel flow.

MrTube · 07-12-2011, 04:00 PM

does that carb have a removable seat like the early Zenith which may have unscrewed with the needle?

Pepsi Mechanic · 07-12-2011, 04:06 PM

Quote:

Originally Posted by MrTube

does that carb have a removable seat like the early Zenith which may have unscrewed with the needle?

Yes it does .... Would the engine run OK though with it out ?...

MrTube · 07-12-2011, 04:12 PM

I highly doubt it

In fact I'd bet it would run really rich.

Pepsi Mechanic · 07-12-2011, 04:33 PM

Sponsored Links (Register now to hide all advertisements)

Quote:

Originally Posted by MrTube

I highly doubt it

In fact I'd bet it would run really rich.

Keep in mind with it threaded all the way in the engine runs ok ..you just crack it open and she runs rich . never did that before . there is definatly an issue with that valve ...

MrTube · 07-12-2011, 04:43 PM

Sure, kind of like it would if the seat was stuck to the needle and simply getting pushed against its own threads when the needle is threaded in. When you unscrew the needle its pulling the entire seat out leaving a huge hole instantly.

I would pull it apart and see if that is the case or not.

Pepsi Mechanic · 07-12-2011, 04:49 PM

Quote:

Originally Posted by MrTube

Sure, kind of like it would if the seat was stuck to the needle and simply getting pushed against its own threads when the needle is threaded in. When you unscrew the needle its pulling the entire seat out leaving a huge hole instantly.

I would pull it apart and see if that is the case or not.

I agree ... thanks for the help ... It does make sense

mrtexas · 07-12-2011, 10:31 PM

Quote:

Originally Posted by Pepsi Mechanic

I agree ... thanks for the help ... It does make sense

There is no screw in seat on a Tilly. It is part of the casting.

http://members.fortunecity.com/pjsauber/TillyCarb.htm

Dave in Boise · 07-13-2011, 11:29 AM

if the screw was really torqued down by the driver, it might have deformed the needle, seat or both. I'd screw the needle all the way out and see if it has a 'stairstep' that might have been pressed into it? If the 2 sides were deformed, it might make it a bit more 'sensitive' to flowing fuel.. Also if it was opened "way" up and the throttle was pushed down creating full vacuum, the passageway in the GAV deep in the carb could have been flushed, allowing a larger volume of fuel to be passed through the now flushed/cleaned passageway.

My 2 cents.. Hope it helps

Pepsi Mechanic · 07-13-2011, 04:35 PM

Everyone's advise is always welcome ... I have a new carb coming in from Mac's for Thursday ... I will swap out the carb and make sure the girl is running ... need it for a major event on Monday ... then I will at my leisure take the old carb apart and investigate the issue ... I have a rebuild kit on the shelf so this way I will always have a spare for a quick change if need be .. She gets driven by a few different people over the year and no matter how many times you explain everything it just does not always sink in ... Thats OK .. thats why I am around ... I love fixing her just as much as driving her

MrTube · 07-13-2011, 05:07 PM

Just be warned, I installed a new carb on our Model A over a year ago so my boss could drive it 2 hours to his house and he ended up broke down with a sunk float. I also fought with the GAV not working right until a few days ago.

All I'm saying is be aware just because its new doesn't mean its reliable or works right.

Pepsi Mechanic · 07-13-2011, 06:20 PM

Quote:

Originally Posted by MrTube

Just be warned, I installed a new carb on our Model A over a year ago so my boss could drive it 2 hours to his house and he ended up broke down with a sunk float. I also fought with the GAV not working right until a few days ago.

All I'm saying is be aware just because its new doesn't mean its reliable or works right.

Know what ya mean ... I thought I would buy a new zenith last year and it quit working the smae day ... thats when I installed the tillotson back on after I rebuilt it ... Hopefuly I will have better luck with the new tilly .. They just started making them a few months ago .. truck just has to drive a few hundred yards on Monday for the Pepsi foundation golf game .. Here's keepin my fingers crossed ... she will run now but I just need a backup

07-12-2011, 03:25 PM	#1
Pepsi Mechanic Senior Member Join Date: Jan 2011 Location: London , Ontario , Canada Posts: 229	Tillotson carb problem I rebuilt Our tillotson over a year ago and she has been working great ... I Had someone else drive her in a parade on the weekend and the engine barely stayed running and was kicking out black smoke ... very rich ... Found out that the person opened the choke control rod CCW a full turn .Not sure why he did that .. I normally run it at a 1/4 turn ... So I turned it back to normal ( 1/4 turn )and she still runs rich ... I had to turn it all the way in CW to make her run better ... Any idea's as to what is or went wrong ? I need to do a couple of small shows over the next week and she should be OK for that ,but should I plan on rebuilding the carb later next week? Has anyone tried the new Tillotson that Mac is selling ?--- I would like to have a spare on the shelf Last edited by Pepsi Mechanic; 07-12-2011 at 03:30 PM.

07-12-2011, 03:51 PM	#2
pat in Santa Cruz Senior Member Join Date: May 2010 Location: santa cruz, calif Posts: 2,011	Re: Tillotson carb problem possibly it was seated too hard before it was turned out a full turn and expanded the orifice. Or, there could have been a speck of dirt in there that washed out when it was fully opened, thereafter allowing greater fuel flow.

07-12-2011, 04:00 PM	#3
MrTube Senior Member Join Date: Jun 2010 Location: New Jersey Posts: 1,471	Re: Tillotson carb problem does that carb have a removable seat like the early Zenith which may have unscrewed with the needle?

07-12-2011, 04:12 PM	#5
MrTube Senior Member Join Date: Jun 2010 Location: New Jersey Posts: 1,471	Re: Tillotson carb problem I highly doubt it In fact I'd bet it would run really rich.

07-12-2011, 04:43 PM	#7
MrTube Senior Member Join Date: Jun 2010 Location: New Jersey Posts: 1,471	Re: Tillotson carb problem Sure, kind of like it would if the seat was stuck to the needle and simply getting pushed against its own threads when the needle is threaded in. When you unscrew the needle its pulling the entire seat out leaving a huge hole instantly. I would pull it apart and see if that is the case or not.

07-13-2011, 11:29 AM	#10
Dave in Boise Senior Member Join Date: May 2010 Posts: 330	Re: Tillotson carb problem if the screw was really torqued down by the driver, it might have deformed the needle, seat or both. I'd screw the needle all the way out and see if it has a 'stairstep' that might have been pressed into it? If the 2 sides were deformed, it might make it a bit more 'sensitive' to flowing fuel.. Also if it was opened "way" up and the throttle was pushed down creating full vacuum, the passageway in the GAV deep in the carb could have been flushed, allowing a larger volume of fuel to be passed through the now flushed/cleaned passageway. My 2 cents.. Hope it helps

07-13-2011, 04:35 PM	#11
Pepsi Mechanic Senior Member Join Date: Jan 2011 Location: London , Ontario , Canada Posts: 229	Re: Tillotson carb problem Everyone's advise is always welcome ... I have a new carb coming in from Mac's for Thursday ... I will swap out the carb and make sure the girl is running ... need it for a major event on Monday ... then I will at my leisure take the old carb apart and investigate the issue ... I have a rebuild kit on the shelf so this way I will always have a spare for a quick change if need be .. She gets driven by a few different people over the year and no matter how many times you explain everything it just does not always sink in ... Thats OK .. thats why I am around ... I love fixing her just as much as driving her

07-13-2011, 05:07 PM	#12
MrTube Senior Member Join Date: Jun 2010 Location: New Jersey Posts: 1,471	Re: Tillotson carb problem Just be warned, I installed a new carb on our Model A over a year ago so my boss could drive it 2 hours to his house and he ended up broke down with a sunk float. I also fought with the GAV not working right until a few days ago. All I'm saying is be aware just because its new doesn't mean its reliable or works right.