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Europa #435 G-RODO Build Journal - 2019 11

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7 Apply masking tape firmly around frayed end of 100-04 hose where it was pulled out of damaged hose-end socket. Cut off the minimum length needed to get it cleaned up again. Fit hose-end, successfully this time, without excessive effort. I note that checking the maximum gap between the nipple nut and the socket with my thumbnail is not a good idea - the nail is a very loose fit in the required 0.031" gap when set with feeler gauge.

Blow out the assembly and fit it to the 4-way cross. I now can't understand why I had positioned the 4-way cross so far to port, making the hose to the port carb so short. It would be better if it was more central or even slightly to starboard, which would result in a shorter hose to the pressure sender and a better route from the fuel pump. Experiment with the shorter hose going to the starboard carb, but that causes the 4-way cross to be aft of the ignition module and so is not practical. That shorter hose might just be long enough to reach to the pressure sensor, though, so it might not be wasted. Temporarily fit the starboard carburettor air filter to see how that affects the hose routings.

The 500mm length of hose I got with the replacement hose-end will certainly be long enough for either port or starboard carb if the 4-way cross is positioned near the centreline, so tape up one end and cut it off cleanly. Fit a hose-end and blow it out. Assemble it to the 4-way cross.

As an afterthought, I wonder if it might be easier in future to do up the nipple nut with a deep socket and a TEE-handle, to get a more balanced pressure on the nut.
3139.6
9 Re-check possible routings of fuel hoses that connect to the 4-way cross. It appears that the shorter length of hose should be OK to reach from the 4-way cross to the pressure sensor, and the older, stiffer length of 100-04 hose will be OK for the section from the fuel pump to the 4-way cross. Tape up one end of that and cut it off cleanly. Find that after getting the hose started into the socket, it's easiest to hold the hose in the VEE of the vise jaws and push the socket fully onto it while turning it with a 5/8" socket. After lubricating with SAE 30 oil, using a 9/16" deep socket with a TEE-handle makes it slightly easier to drive the nipple home, and results in less damage to the anodizing too. 3140.1
12 Lay the length of stiffer 100-04 hose with the hose-end fitted over the top of the engine. Connect the hose-end to the 4-way cross, and with the other 3 hoses routed as desired, check the length required to reach the fuel pump nipple. Mark the hose, tape at the mark, and cut off with Dremel wheel. Blow out and re-check length. Lubricate with SAE 30 oil and try fit of hose on pump nipple. Starts quite easily but becomes very hard to push as nipple gets further into hose. Stop trying as don't want to expand braid un-necessarily.

Now with all 4 hoses in place, check length of run to carburettors. Starboard one can be shortened quite a bit; mark it for cutting. Port one seems OK as is.

Returning to a previous thought about shoe-horning the hose into the cover clamp, try wrapping a small piece of thin PTFE sheet within the cover clamp to form a slight funnel shape. Try pushing an offcut of hose into it but no joy as the fit is very tight and even with the end taped up the ends of the braid dig into the plastic and prevent the hose sliding in.

Tape the starboard carb hose at the mark and cut it. Note that it is much easier to get a clean cut if a rough cut is first made just beyond the required point. There is then no protruding hose to interfere with the movement of the Dremel and prevent the disc cutting squarely all round.

Measure the distance between fitting on all the braided hoses for firesleeve.

4-way cross to pressure sensor: 295mm
4-way cross to stbd carb: 345mm
4-way cross to port carb: 475mm
4-way cross to pump: 465mm
Pressure sensor to FRFF: 45mm (100-04 hose but firesleeve will need to be much larger to go over hose-ends)
Firewall elbow to pump: 790mm (100-06 hose)

100-04 hose is 12mm OD so 0.5" firesleeve will be OK. A total of 1580mm (5 feet 2.2 inches) is needed in that size, so should order 6 feet of AE102-8 as LAS Aerospace charge to next foot and it will be good to have some spare just in case.
100-06 hose is 14.5mm OD so need 0.625" firesleeve. Need to order 3 feet of AE102-10.
101-04 hose-end is 17.5mm at greatest OD and to go over that will need a foot of AE102-12 (0.75" ID).

Place order with LAS Aerospace for above firesleeves, plus some rivets and anchor nuts. No need to order clamps as I have plenty of stainless steel tie-wraps in stock.
3141.4
13 Order from British Chemical Products some toluene for diluting hi-temp RTV to soak into ends of firesleeve.
14 Firesleeve etc delivered from LAS Aerospace .
18 Collect toluene from British Chemical Products in Cinderford.
21 Squirt out a length of hi-temp red RTV silicon sealer into a mixing cup and add some toluene. Need only a small amount of toluene at first, to get it into a smooth paste, before diluting further. When it seems uniformly liquid, cut off a short length of the AE102-12 firesleeve and dip the end into the diluted RTV. Seems to soak in quite well, although obviously I can't see into the glass matrix. Try thinning the mixture a little more with toluene, and dip the other end of the offcut into that. Clean the RTV off the outside of the firesleeve and mark the latter end "thin". Leave it to cure.

Try sliding the AE102-10 firesleeve onto the prepared elbow-to-pump 100-06 hose, from the pump end which is taped up. It starts without much trouble, but soon gets hard to push on. Start the air compressor and poke the fine air-gun nozzle in between the hose and the firesleeve. That inflates the firesleeve slightly and makes it really easy to slide on, although it would work better with 3 hands. The same technique also gets the firesleeve off the hose again quite easily.

Check the other sizes. The AE102-8 firesleeve starts easily onto the end of the 100-04 hose - might not even need airline help, and the AE102-12 firesleeve goes over a 101-04 hose-end with no effort.
3142.1
22 The dipped sample of firesleeve seems to have cured OK. Cut it apart to check penetration - not very much, really only red on the surface, and not much difference between the 2 ends. Cut in half and leave one piece in the jar of (now quite dilute) RTV-toluene mixture. After several hours take it out and leave to dry.
28 The RTV-toluene mixture seems to have penetrated a bit more on the longer-soaked sample of firesleeve, so it seems OK to proceed.

Check length of AE102-10 firesleeve needed for 100-06 firewall to pump hose. Cut slightly longer than the distance between the fittings so that it will overlap the fittings slightly.

Squirt some high-temp red RTV into a mixing cup and to it add a little of the previous RTV-toluene mixture that was stored in a glass jar, mixing into a smooth paste. Gradually add the rest of the mixture until it is smooth and well-mixed. Decant it into the glass jar.

The firesleeve tends to have a flat section from being coiled up. Fit a releasable cable tie to each end of the firesleeve to encourage it into a more circular shape. Form into a horseshoe shape and insert both ends into the glass jar until they touch the bottom, with about 10mm immersed, and leave to soak.

Trim off the untidy end of the AE102-8 firesleeve. This will be used on the 4 pieces of 100-04 hose that connect to the AN827-4D 4-way cross. Check length required against the shortest piece of 100-04 hose (the return line) and as before cut off a piece of firesleeve to overlap end fittings slightly. Similarly cut firesleeve lengths for the pump (long, stiffer piece of hose); starboard carburettor (shorter flexible); and port carburettor (longer flexible). Mark each length of firesleeve for identification. Fit a small cable-tie to each of the ends to keep them more circular.

The AE102-10 firesleeve has had a good while soaking so take it out. Wipe excess off the outside and re-form the ends which have gone rather oval again. Hang it up to dry.

Put the 4 lengths of AE102-8 firesleeve into the jar of RTV-toluene mixture and leave to soak.

About half an hour later, return and remove the lengths of firesleeve, wipe outsides clean and put other ends into jar of mixture.

Later again, remove all 4, wipe outsides clean and leave to dry. There is not much mixture left, most of it has been soaked up into the firesleeves.
3143.6

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