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Carb jets frozen on their bores

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Scott S	Dec 22 2009, 10:19 AM Post #1
Small Member Group: Members Posts: 1,697 Joined: 30-April 03 From: Colorado Member No.: 633	Hi All – . I have a 2.7 that will be running carbs (40IDTP). They were fully gone through, the shafts are great, and they are very very clean. Last night I was going through parts and decided to pull the air/emulsion tubes just to see what they had in them (the carbs came from sea level and I am in Colorado – around 6200 feet). It was everything I could do to get the jet to turn/unscrew in the bore – I could not believe how stuck they were. I didn’t even attempt to do the second carb – just sprayed the thing with carb cleaner and let it set over night. Is this normal? Once they broke free, they were very easy to turn and the emulsion tubes came right out – unfortunately the top of the brass jet where the screw driver rests is now gnarled. I have a modified screw driver that is the correct thickness for the slot in the jet, and that was ground on the sides to fit into the bore on the carb. Being that I am sure there will be some trial and error in getting this motor jetted correctly, is there a way to prevent this in the future? On my current -4 motor I am running dual 40’s and have never had this happen in 10 years – every thing comes a part very cleanly (the car only has 10k miles on a 1996 rebuild however…) Thanks for any help! (IMG:style_emoticons/default/santa_smiley.gif) Scott S

McMark	Dec 22 2009, 10:22 AM Post #2
914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None	That happens when carbs are left sitting for a long time. Just corrosion gumming up the works. To keep them lubricated, just drive it! (IMG:style_emoticons/default/driving.gif) (IMG:style_emoticons/default/mueba.gif)

r_towle	Dec 22 2009, 12:40 PM Post #3
Custom Member Group: Members Posts: 24,574 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States	Dunk them in Carb cleaner overnight. Rich

brant	Dec 22 2009, 12:55 PM Post #4
914 Wizard Group: Members Posts: 11,625 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains	Scott, it probably won't happen again I'm guessing its bi-metal type corrosion or varnished fuel but you should be fine now what jets did you find in there?

Scott S	Dec 22 2009, 01:01 PM Post #5
Small Member Group: Members Posts: 1,697 Joined: 30-April 03 From: Colorado Member No.: 633	QUOTE(brant @ Dec 22 2009, 11:55 AM) Scott, it probably won't happen again I'm guessing its bi-metal type corrosion or varnished fuel but you should be fine now what jets did you find in there? Hi Brant! The emusion tubes are F1's and I think the airs are 170's? It's hard to tell with the gnarled tops. It appears there are no main jets installed. What are you running on your race car at our altitude? Is it weird that I enjoy looking at these things so much? Those three dirty gold velocity stacks get me all twitterpated.... (IMG:style_emoticons/default/biggrin.gif)

brant	Dec 22 2009, 01:08 PM Post #6
914 Wizard Group: Members Posts: 11,625 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains	QUOTE(Scott Schroeder @ Dec 22 2009, 12:01 PM) Hi Brant! The emusion tubes are F1's and I think the airs are 170's? It's hard to tell with the gnarled tops. It appears there are no main jets installed. What are you running on your race car at our altitude? Is it weird that I enjoy looking at these things so much? Those three dirty gold velocity stacks get me all twitterpated.... (IMG:style_emoticons/default/biggrin.gif) My jets will be way way off for you the race car won't run below 5grand, but we gear it to work that way I'm running about 160 mains, with another 50count of added 2ndary enrichment so way way way large... but your motor is big so there should be lots and lots of 2.7 advice out there ask greg, what eurosport put into his 2.7 for jetting also ask lars what he is using for a 2.7 in boulder (also a lot of pelican knowledge out there too) brant

VaccaRabite	Dec 22 2009, 01:36 PM Post #7
En Garde! Group: Admin Posts: 13,444 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region	The IDFs thta I tore apart were the same way. Lots of varnish and come corrosion to boot. Zach

r_towle	Dec 22 2009, 01:53 PM Post #8
Custom Member Group: Members Posts: 24,574 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States	QUOTE(Scott Schroeder @ Dec 22 2009, 02:01 PM) QUOTE(brant @ Dec 22 2009, 11:55 AM) Scott, it probably won't happen again I'm guessing its bi-metal type corrosion or varnished fuel but you should be fine now what jets did you find in there? Hi Brant! The emusion tubes are F1's and I think the airs are 170's? It's hard to tell with the gnarled tops. It appears there are no main jets installed. What are you running on your race car at our altitude? Is it weird that I enjoy looking at these things so much? Those three dirty gold velocity stacks get me all twitterpated.... (IMG:style_emoticons/default/biggrin.gif) to funny...no main jets...did it run a little rough??? Rich

ME733	Dec 22 2009, 04:23 PM Post #9
Senior Member Group: Members Posts: 842 Joined: 25-June 08 From: Atlanta Ga. Member No.: 9,209 Region Association: South East States	(IMG:style_emoticons/default/popcorn[1].gif) CAUTION!!! if it,s clean quit using carb cleaner.! , you are removing any (oil) lubricant for the carb body threads, and promoting OXIDATION between the two seperate metals. carb/ jets. You could strip out the threads in the carb body. The Parts need s o m e lubricant in/at the threads. Use some "nut breaker loose" or kerosene as a lubricant/soak to loosen the parts. The jets that have been "dinged up" by a too small screwdriver ......must be replaced. air/ fuel flow will not be "normal", as smoothness is important for jets to work as designed. Find the proper jet drill size,that fits, to determine what you have.(the dinged up ones you cannot read.). installing / determining the best jets for your engine could be a challenge. If you know a lot about it,.... displacement, compression,pistons, cams, heads, and carb type/ venturis size...a good 911 engine guy is going to be your best resource. (IMG:style_emoticons/default/popcorn[1].gif) for your consideration Murray

Scott S	Dec 22 2009, 04:49 PM Post #10
Small Member Group: Members Posts: 1,697 Joined: 30-April 03 From: Colorado Member No.: 633	QUOTE(r_towle @ Dec 22 2009, 12:53 PM) QUOTE(Scott Schroeder @ Dec 22 2009, 02:01 PM) QUOTE(brant @ Dec 22 2009, 11:55 AM) Scott, it probably won't happen again I'm guessing its bi-metal type corrosion or varnished fuel but you should be fine now what jets did you find in there? Hi Brant! The emusion tubes are F1's and I think the airs are 170's? It's hard to tell with the gnarled tops. It appears there are no main jets installed. What are you running on your race car at our altitude? Is it weird that I enjoy looking at these things so much? Those three dirty gold velocity stacks get me all twitterpated.... (IMG:style_emoticons/default/biggrin.gif) to funny...no main jets...did it run a little rough??? Rich I am thinking it probably ran a bit rich! Ha!!

Gint	Dec 22 2009, 05:58 PM Post #11
Mike Ginter Group: Admin Posts: 16,075 Joined: 26-December 02 From: Denver CO. Member No.: 20 Region Association: Rocky Mountains	D'oh! Sorry Scotty. Everything working out OK? How'd you like those headers? Are those beef or what?

Scott S	Dec 23 2009, 10:11 AM Post #12
Small Member Group: Members Posts: 1,697 Joined: 30-April 03 From: Colorado Member No.: 633	Hi Mr Gint! I wont know if all is well until we fire her up. But as we both know, the seller is a top notch guy, so I am not really concerned at all. Those headers are bitchen! I have no idea what they are, and quite frankly, I dont care. I did a test fit and I will have to change out the exaust studs (that makes me a bit nervous...snap). Oh, that brings up another question... I want to run the PMO spacers, and will most likely just be using the stock manifolds. Where is the best place to get the different length exaust and intake studs? Merry Christmas everyone - we got a white one this year............ (IMG:style_emoticons/default/santa_smiley.gif)

Gint	Dec 23 2009, 10:15 AM Post #13
Mike Ginter Group: Admin Posts: 16,075 Joined: 26-December 02 From: Denver CO. Member No.: 20 Region Association: Rocky Mountains	I got my last few studs from Raby.

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