by Phil Lindsay

In order to better cope with the California gas lines, I have installed an extra gas tank in my Tiger. My additional tank comes from the early series Alpine I or II. The tank is a horizontal unit, which holds approximately 12 gallons and can be mounted in the flat region of the Tiger trunk. The extra tank is installed in such away that it fills and empties along with the two stock side tanks. Although the trunk space is reduced, I am able to carry lots of spare parts, four toolboxes, and a spare tire, and still have room for an airlines carry-on suitcase.

The first step involves relocating the battery from the stock Mark I Tiger location (right side of trunk) to the spare tire well. This operation requires a little metal bending and hammering to put a flat bottom on the well. I covered the area with fiberglass cloth and resin for reinforcement. The Alpine tank has a filling pipe on its right side and a fuel pump feed line connection in the center of the bottom back edge. In my installation, the tank mounts “upside down” so that the filling neck points towards the rear bumper and the pump connector is on top.

Fig. 1

The filler neck is then connected to the main gas line between the side tanks. The pump connector becomes a vent and ties into the side tank vent line. I had my local radiator shop boil-out and leak-test the tank. Once cleaned out, the shop repositioned the filler neck so that a “tee” connection could be made into the main gas cross line. I found that copper plumbing fittings can be purchased with an outside diameter that slips inside the stock rubber couplings. A detail of this set-up is shown in Photo #1.

Fig. 2

As shown in Photo #2, the tank is positioned between chassis rails using pieces of steel angle channel. The channels straddle the chassis rails and the tank bolts to the channels with its existing bolt holes. In order to use the space surrounding the sides of the tank, I used masonite panels to partition the area into storage bins.
The tricky part of the installation is positioning the tank so that there is enough vertical clearance for the spare tire. Once this location is established, it is necessary to determine the correct combination of copper tees and short nipples to make the connection between the tank and the main gas cross line. In my installation the very bottom of the horizontal tank (less than 2 gallons) is positioned so that it doesn’t drain out. This could be corrected by mounting the tank higher, but then there would be no room for the spare tire.

Fig. 4

Photo #3 shows the various storage areas. There is lots of room for spare hoses, parts, and toolboxes. I modified the false bottom by taking out the battery hump. As shown in Photo #4, the false bottom fits over the tank and permits storage of the spare tire.

Fig. 4

I have been using the system for over a year with no problems. Although there is no improvement in gas mileage, my driving range has doubled. I find that the stock gas gauge is accurate at the extremes (empty and full), however, the readings in the mid-scale are not linear. Obviously, it is extremely important to properly connect the tank to insure leak tight fittings. I suggest that new OEM rubber couplings (available from Sunbeam Specialties) and stainless steel worm clamps be used. The vent hose must be rated for fuel service.

I am a little concerned about rear end collisions (a la Pinto!) but the stock Tiger set-up is so bad due to the vulnerable cross-pipe mounting, that I doubt that the extra tank is much worse. I have installed an impact-sensing switch on the electrical fuel pump circuit in order to shut off the pump in the event of an accident.

Related posts:

1. Crud in the Fuel Tank
2. Fuel Line: A Nasty Design Problem
3. Fuel Tanks

by Bill Rosenbusch

Don’t get stuck on the way to a Tiger get?together in hot weather due to vapor lock at the fuel pump. THE CURE ? Obtain one piece of foil?backed fiberglass ceiling insulation approximately 18″ by 24″ and wrap it around the right side muffler (under the fuel pump, foil side out and fix it in place with racers’ tape or mechanics wire.

Related posts:

1. Adding an Inline Fuel Filter to Series V
2. Crud in the Fuel Tank
3. Fuel Line: A Nasty Design Problem

by Steve Finberg

As much as it surprises most U.S. mechanics, the Limeys painted the insides of our gas tanks! This paint is now starting to flake off (at least on my 3 cars and several others in New England). Don’t get me wrong, I am not complaining. Everyone with whom I have talked thinks paint would not last a few weeks in a gas tank, let alone more than 15 years. In fact, the paint is not dissolving but rather is losing its affinity to the metal. The paint flakes off and tends to clog the cross pipe to fuel line connection. This can lead to many confusing problems, but primarily it results in gas starvation. Before the line is totally clogged only a trickle can get through. This may be enough at idle or around town, but can lead to overheating or stalling at speed as the carburetors are forced to run very lean. Eventually the line will clog completely, either at the cross pipe or at the fuel pump. I have seen a fuel pump changed only to have the problem reoccur in a few weeks.

In an Alpine, the first sign of a problem will be the small black curly flakes in the fuel pump bowl. However, this is not where the system usually clogs. The clogs occur at (1) the right angle inlet to the fuel pump (fixed with an in?line gas filter), (2) at the junction of the gas line to the cross pipe at the gas tanks.

The blockage at the fuel pump can be cured by removing the fuel line and pushing out, with a small wire, from the pump bowl. The blockage at the cross pipe can be cured only temporarily with compressed air, by blowing it out from the fuel pump end. It will generally return within 10 to 20 miles. A slightly more permanent fix requires removing the gas line at the cross pipe and pulling the crud out with a hooked wire. Be prepared for a slight trickle of gas as the line is first removed, and a major flood as the blockage is removed.

Unfortunately this is only a temporary fix, as the paint flakes off slowly and will block up again sooner or later. Watch the filter for first signs. It seems to clog sooner in the summer than in the winter.

A permanent fix requires removing the fuel tanks and stripping off the inside paint. This is easier said than done. My first approach was to take the tanks to the local radiator shop. The owner assured me that one day in his tank would rot out any paint completely. A week later, only about 80% of the paint had been removed, the rest looked slightly flaky. He didn’t think much more would come out, and I think he wanted the space back. Next I tried several paint removers and solvents available in my lab, but none even touched the stuff. Finally, I took a length of sharp edged window sash chain and shook it around inside the tank. A thorough shaking removed the rest of the paint. I then washed the tank in water to remove the loose flakes and dust, and any remaining radiator shop fluid residue.

A thorough inspection of the tanks and cross pipe (with paint removed) revealed several pinholes, which may have been blocked by the paint. I brazed them shut. The exterior was then wire brushed, primed and painted gloss black.

In the week between the washing and the planned installation, the tank showed some slight rust. I decided to coat the inside with “Hirsh” gas tank sealer, as advertised in Hemmings Motor News. It is advertised for coating rusty antique gas tanks, and supposedly seals any rust and plugs pin holes. It is a yellow, very sticky paint, which, when applied and sealed in a tank, exerts quite an outward pressure, forcing it into any pinholes or seams. The company assures me that it will not flake off or dissolve. As I have just finished so I cannot yet report any results.

A convenient time to inspect the wells for accumulated dirt and rust, and to restore the inside paint is while the tanks are out. This makes body work in that area so much easier.

To get around temporarily while the main tanks are out, a marine tank can be connected to the fuel pump or filter. An inexpensive one for this purpose is the Sears Game Fisher Tank.

Editors note: The gasoline in the fuel tanks should be siphoned out before cutting or disconnecting the main fuel line to eliminate draining gasoline on the ground or your garage floor.

Related posts:

1. Adding an Inline Fuel Filter to Series V
2. Fuel Tanks
3. Fuel Line: A Nasty Design Problem

by J. Charles Watamess

If you own an Alpine, you may have noticed the fuel line from the tank to the engine is a single piece of formed steel tubing. In most English cars, you will find a piece of flexible hose connects the solid line from the tank to the inlet of the fuel pump. I recently had this line fail right at the fitting where it enters the pump. Fortunately for me, it happened in my driveway and was not serious. However, when it fails, the entire contents of the fuel tank siphon all over the ground.

Last evening, I heard of someone with an Alpine that recently had the same failure. Unbeknownst to the driver, the fuel had spread across the bottom of the car. Upon stopping at a traffic light, it ignited under the hood causing an explosion. The siphoning gasoline fed the fire and the car was completely destroyed.

The easiest solution to this problem is to make a stub piece of tubing for the fuel pump inlet. The main fuel line should be cut back near the frame and a length of neoprene hose should be inserted between the two using high quality clamps. Be careful when cutting the lines. Under no circumstance should you use an incandescent trouble light. A couple of years back, I was removing an inlet line to a fuel pump and splashed some gasoline on a trouble light that broke and set both me and the car on fire. To make matters worse, the continual flow of gasoline fed the fire. In was extremely lucky in being able to extinguish it, but before, I could do so, extensive damage had been done to the car.

It is always a good idea to have a fire extinguisher immediately at hand when working on the fuel system.

Editors note: The gasoline in the fuel tanks should be siphoned out before cutting or disconnecting the main fuel line to eliminate draining gasoline on the ground or your garage floor.

Related posts:

1. Adding an Inline Fuel Filter to Series V
2. Crud in the Fuel Tank
3. Cool Fuel

Editors note: This warning, from a Rootes Service Bulletin, is important to Tiger owners who still have the original oil filter location.

Subject: High Pressure Line Failure

Isolated cases of failure, of the high pressure oil line, top of oil filter to cylinder block, have been brought to our notice due to chafing of this pipe against the universal joint of the steering column.

This, if allowed to continue, could eventually cause break-through of the hose and complete loss of oil.

Will all addressees please bring this to the attention of all service personnel, to ensure that on P.D.I., 500 mile free service, or at normal servicing periods, the clearance between the oil filter pipe and the steering universal joint is sufficient to prevent this chafing.

ROOTES MOTORS INCORPORATED
KENNETH LANGRIDGE
GENERAL SERVICE MANAGER

Related posts:

1. Bulletin 67-42: Tiger Modified Oil Filter Line Attaching Point
2. Bulletin 60-188: 1,000 Mile Inspections
3. Fuel Line: A Nasty Design Problem

by Bob Pennell

When the tanks were removed from the car, there had been no leaks. Upon inspection, there appeared to be only superficial rusting on the bottom. So, I wire brushed and sanded to bare metal, then metal prepped before priming and painting. The interiors were coated thoroughly with Bill Hirsch gas tank sealer, and the tanks reinstalled in the car.

As soon as the tanks were filled with gas, the left side began to leak at the rate of about one cup per hour. Suspecting a loose connection at the balance pipe, I removed the trim panels and felt around under the hose connections, but no leaks were evident here. So, out came the left side tank, and external inspection uncovered no obvious point of leakage. The tank was dried out, and another application of the Hirsch sealer added. This time, the tank was partially filled with gas and allowed to sit for several days outside of the car. No leaks, so back in the car it went and everything was buttoned up in the trunk area.

Several weeks elapsed, and then the dripping started again, this time at a slower rate than before. Upon removal a second time, a pinhole was evident at the bottom of the tank where a small amount of sealer also had bled through.

Enough fooling around, I thought, and the tank was sanded down to bare metal and the entire bottom encased with fiberglass cloth and epoxy resin, then repainted and reinstalled. So far so good, no leaks the third time around. The right side will probably start any day now, the way my luck seems to run. The point of this is simply if you observe any surface rust at all on the bottom of the tank, don’t mess around with glass!

Editors note: Pinholes can be soldered or brazed and then sealed with many of the new gas tank sealers now on the market.

Related posts:

1. Crud in the Fuel Tank
2. Fuel Line: A Nasty Design Problem
3. Adding an Inline Fuel Filter to Series V

This is the one that gets forgotten most often at tune?up time. It’s the fuel filter. Also, to be on the safe side, change the short connector hoses. These can look good but actually have small cracks in them. No under hood fires, please.

Related posts:

1. Adding an Inline Fuel Filter to Series V
2. Bulletin 67-42: Tiger Modified Oil Filter Line Attaching Point
3. Remote Oil Filter

author unknown

If you have a dual carb-equipped car such as an Alpine I through III, an Alpine V or an Alpine GT, there might be some fine points you have missed in the course of tune-ups. Dual carbs are no great secret: all they take is some care and TLC. But if you neglect them, you will find your vehicle is running like a Mack truck and sounding like a boiler factory when it’s idling.

One thing to look for is poor throttle synchronization. With an older car, the passage of time causes damage and wear on the throttle linkage. It’s absolutely imperative to make sure both throttles are opening evenly and at the same time. Make sure they both open fully, and toy around with the linkage between the carbs until you have them opening at exactly the same instant. It takes a little attention, but it pays dividends. The Alpine V Stromberg linkage is particularly prone to problems here.

Another thing that is often overlooked is ensuring the various components are making a tight and leak-free seal. The Zenith carbs on the Series I through III often worked loose, or the manifold would vibrate free just a tad. It might not be obvious but it would be enough to cause a manifold leak with constant problems. The Stromberg manifold is much shorter and better angled to avoid this, but it still bears checking out. Check all carb and manifold mounting bolts with a wrench and snug them down securely but not TOO tight, as both carb and manifold are aluminum and can be warped.

Also, the workshop instructions on adjusting strangler (choke) controls are suspect. Both Zenith and Stromberg (actually the same people!) have backed off from the “drill in the throttle plate method” in recent years and have simply stated that the best way to adjust your choke is by ensuring that it advances the idle to the “reasonable” speed. With the Alpine I through III, 1000 rpm is probably a satisfactory idle speed. With the Series V and GT, 1500 rpm is probably good. You should try to find the speed at which your car will idle evenly under cold conditions with the strangler out. Due to wear on the engine and carbs, no two engines will have exactly identical solutions, but the above values give you something with which to work.

Balancing dual carbs is a tremendous shibboleth that is actually not at all the arcane secret it’s supposed to be. Use a Uni-Syn or similar tool if it’s available. If not, use a 1/4 inch rubber hose to listen to the hiss at the air intakes. (WARNING: The PSW tool kit method of comparing piston rise simply isn’t accurate enough. Why spend $7.95 for something that’s not good enough? What you’re trying to do is to ensure that both carbs are drawing evenly. It doesn’t have to be exact, just in the ballpark. Try it a couple of times to get it worked out and you’ll find it’s really not that hard. I recommend you take the air cleaners off and run the engine hard for a twenty minute run to get the engine warmed up nicely, then work fast. The closer to actual road conditions you are, the more accurate your work will be.

Dual carb setups are more sensitive to throttle shaft wear than are single carbs, and it’s important that your exhaust be in reasonably good condition. Double-check your linkage when you are finished to ensure that the throttles are precisely even and open simultaneously. That is, once you’ve balanced the carbs and set mixture strength, go back and make sure both carbs open and close at the same time.

You also should balance your carbs at fast idle. That is a fine point even the workshop manuals leave out. Pull the strangler out, check the balance, and toy around with the linkage to make sure both carbs are drawing evenly.

Watching for these few points should improve your idle quality considerably and should improve your car’s response, mileage and performance. Dual carb setups are superb and are a fine solution to the problem of fuel metering, but they do require some owner attention to detail at tune-up time!

Related posts:

1. Ford Carburetor Identification 101
2. Bulletin 68-14: Zenith C.D. Carbs Loss Of Oil From Dash Pots
3. Bulletin 67-43: Borg-Warner 35 Thumping Noise

Autolite 2 barrel tuning

By John Logan

Published first in Rootes Review, 2006

The following holds true for any stock Ford carburetor, 2 barrel or 4 barrel.

To identify your carb you need the Ford tag number which is stamped into a triangular shaped aluminum tag under one of the fuel bowl screws. The numbers on that tag are the carb identification number, the design code and the production date code. The identification number is also stamped into the carb base plate in front of the throttle lever. You should compare these 2 numbers; they should be the same, if not, you need to go by the number on the base plate. Another number you want to record is the venturi diameter; this number is cast into the fuel bowl on the left front side above the identifying number.

The stock 2 barrel carb on any 260 engine has a 17/16″ bore diameter with a 1.01″ venturi diameter; this is the only size listed for the 260. The 289 carb had venturi diameters of either 1.02″, 1.08″ and 1.14″; the 302 had 1.08″only.

If you are rebuilding your carb, that identifying number should be listed on the rebuild sheet along with some of the settings. I prefer to use Mustang and Ford Small Block V8, by Bob Mannel, as my reference source. It is an excellent source of information on all Ford Small Block part numbers and there is a separate section on Ford carbs with a complete listing of the stock setup, specifics, settings and adjustments listed by carburetor identifying number.

I have one 2 barrel carburetor that has no identifying tag; the number on the base plate is C3AF BE with venturi diameter of 1.01. This is a 1963 carb for a 260 engine. The 2 barrel carb on my Tiger has a tag # C7DF R and B 7CB with venturi diameter of 1.14″.
C7DF R identifies this as a 1967 carburetor. B 7CB = design B; Production date – 7 = 1967, C = March, B = 2nd week. This is a replacement carburetor that someone installed on the engine.

Stock Tiger 2 barrel carburetors as listed in the Rootes Parts Manual:

.

I have very little information about the Stock MKII 2bbl carb. Tag number C5ZF-H is listed in the Mk II parts manual, and #C6DF-A is listed in the Shop Manual.

I found very little data CFM volumes for 2 barrel carbs, so I made some best guesses as noted for this chart.

Basic carburetor tuning

To get the best fuel mileage out of your carb it needs to be in good working shape. The moving parts must be free to move. All the gaskets need to be in good shape with no deterioration. Your goal is no fuel leaks, no wet spots and no vacuum leaks.

Refer to the Tiger Shop Manual for a general description, set points and adjustments for your original carb; if you do not have an original carb then you need a spec sheet for your carb. The Shop Manual is a good starting point if it is the only reference information you have available.

Start off with the Engine cold. Examine your carb and check all the linkage for ease of movement; lubricate as needed. Check all the carb gaskets for wet areas and deterioration, especially the base plate and the carb top cover gasket. Replace gaskets as needed.

Run just the fuel pump to fill the fuel bowl; listen to the fuel pump; make sure it stops pumping after a few seconds. If the pump does not stop; shut it off and look for the leak; fix any leaks first.

Look down the carb; it should be dry down the bores; if it is wet, most likely the fuel level is too high or the fuel pressure is too high. Check the fuel pressure with a fuel pressure gage.

The stock Ford fuel pressure range for the Autolite 2bbl is 3.5 to 5.5 psi. I believe, but have not confirmed, that the Tiger electric fuel pump’s range is 2 psi. This is OK if you have no highway speed problems.

Remove the carb top cover and check the wet fuel level with a metal rule; many 2bbls are around 3/4” wet. This is where you need a spec sheet to match up with your carb ID number.

If the float has sunk; replace it. Brass floats can be repaired with solder but be very careful about getting all the gasoline and fumes out of the float before applying high heat or flame. Safety first.

Set the correct fuel level if needed. Fuel level set just a little low is better than too high.

Put the carb top cover back on and pull the throttle lever while looking down the carb; check that the accelerator pump squirts fuel equally into each bore.

Settings

Choke cover – many are set at 2 notches rich. For fuel economy the choke must be fully open when the engine reaches operating temperature; adjust your choke according to your specific location.

Set the choke and start the engine. Fast idle – 1200 to 1300 rpm I think 1200 rpm is fine.

Engine operating temperature is 180 degrees F. You are using a 180 degree thermostat, right?  Watch the choke plate as the engine warms up; make sure it opens all the way.

Move the throttle a little; it should come off Fast Idle, down to idle speed. If not; check and fix any binding linkage.

Idle Mixture

For an initial set point, lightly seat each needle screw, then back each out 1 ½ turns. You can use a separate rpm meter to set Idle Mixture or do it by ear. Slowly turn one idle mixture screw out until the rpm drops off; then turn the screw in until the rpm drops; then turn the screw back out to just the maximum rpm point. Do the same with the other idle mixture screw. You are looking for the best rpm with the idle mixture screws turned out the least amount.

The shop manual states that idle speed should be from 575-600 RPM. The lowest I can get with my engine setup is about 800 rpm. Use your judgment here to set your idle speed.

Carb Rebuilding Tips

The following information should be recorded for future reference:

• Tag number on the aluminum tag
• Carb number on base plate
• Venturi diameter
• Jet size number
• Power valve number – if it is marked; some are color coded as listed in the Shop Manual

Disassemble, inspect and clean all parts thoroughly; replace any worn parts. Check the base plate gasket surface for flatness. Also check the flatness of the spacer plate under the carb, the accelerator cover and the power valve cover.

It is very easy to over torque the screws for these parts and warp them. If any of them are warped; you need to make them flat again; here are some options:

Put the cover in a press and use just a little pressure to get them flat or just a bit flatter.
Put fine sandpaper on a flat surface plate and gently wet sand with light oil until the surface is flat.

I use 400 or 600 wet/dry sandpaper.
Buy new parts

Do not over torque any of the cover screws. Your goal is no fuel leaks, no wet areas and no vacuum leaks.

Higher Tech Tuning

This requires a wide range O2 sensor and a means to record the numbers and other variables while driving; or a chassis dynamometer would be helpful. This information will give you when and under what conditions the engine is running rich or lean. This is where you can determine with certainty if the jets are the wrong size or the power valve is opening too early or too late.

Reference sources:

• Mustang and Ford Small Block V8 by Bob Mannel
• Sunbeam Workshop Manual
• Rootes Parts List Publication No. 6601131 with Ford part numbers
• Rootes Parts List Publication No. 6601334 with 289 parts list

Technical articles

www.fordmuscle.com
This is a subscription site so not all the articles can be read without subscribing.

www.tigersunited.com
Technical articles, shop manual, Rootes Parts Manual

Related posts:

1. Water Pump Dimensions – Tiger
2. Engine Mounts
3. Making the Small Block Ford Even Smaller

NUMBER: 68-14
DATE: 6-27-68
GROUP: Fuel
SUBGROUP: Carburetor

MODELS: All Models Equipped With Zenith C.D. Carbs
SUBJECT: Loss Of Oil From Dash Pots — Zenith C.D. Carbs

Where complaints are received of persistent loss of oil from carburetor dash pot pistons resulting in loss of piston damping, it is recommended that the following action be taken:

1. Remove damper(s) and chamber cover(s).
NOTE: Always be sure that the chamber cover is refitted in its original position, otherwise re-centralization of the jet will have to be carried out.

2. Mark and drill a l/16″ (1.5 mm) hole in position shown. Make sure that the hole is drilled so that when cover is replaced, the hole is facing away from the engine, (i.e. the highest point on angled carburetors). The hole must break through into recess above top thread. (fig. 1)

3. Plug the existing hole, with Solex Plug, Part No. 51550. Be sure it is adequately secured and that it does not obstruct the top thread.

4. Refit cover to carburetor. Fill damper with correct grade of engine oil as per Service Manual. Re-fit damper.

J.J. Rivers
Service Manager

Related posts:

1. Bulletin 67-62: Alpine V & Arrow Change of Float Material In Carb
2. Some Hints on Dual Carbs
3. Bulletin 66-2: Tiger 260 Carburettor Modification