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Discussion Starter #1
Hi All,

Just a quick question I'd appreciate some advice on.
I'm about to change the rubber carb mounts on my Sprint.

I've done this before, but with the engine-out on the bench (during my rebuild), so am just wondering if I'll now have to take off the inlet manifold as well to do this properly?

Hopefully I wont and this is just an airbox off, carbs off, mounts off job, but concerned about access to the lower bolts when re-fitting. Any thoughts?

Many thanks for any of your experiences gained over the years to keep this job to a mornings work, rather than a whole weekend.

Marc
 

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Marc

Should be easy I only have experience of 2600's with Solexes and 105 alfa's with dellortos

You should not take the manifold off unless you suspect the gasket is leaking. do this after the carbs are off.

2600 I remove the lot by undoing the carbs to manifold nuts plus staybar nut sounds simple except for one small problem - you have to have a lower arm about 50% longer than a normal human being. After about 3 hours of BS&T it should come off easlily. There is mention elswhere of using and obstruction spanner , cranked handle .

My 2000 105 is the other end of the spectrum dellorto cars with K&N filters. Filters 2 mins carbs no more than 10 minutes. Leaving a couple of hours to do the mounts. I guess your 2000 iron block should be similar

cheers

Ian
 

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As Ian notes - it's no sweat on the 102. Tons of room, and short enough you can reach the rear carb by reaching under from the front.

Your arms will eventually have a nice pattern of scars along the upper surface, but I'm told some women like this look.
 

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Discussion Starter #4
Great. As hoped. Good news! Thank you both.
Will report back with shiny photos or something.
 

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Do it the easy way

Hey, just use a nice 14 mm box end and take off the eight nuts holding the mounts to the intake manifold (plus the one on the bolt holding up the arm from the motor mount) and remove mounts, carburetors and cold air box all in one piece. Piece of cake. Keep the carburetors on the cold air box (and don't undo the choke cables) and just pull the carbs back into the fender enough to take the mounts off them and replace them. Then bolt right back on.

But a suggestion: Use coppercoat (coppercote?) on the paper like gaskets (both sides of both sides) to avoid air leaks. Won't stick to ruin the gaskets, isn't messy (if you don't overuse), and yet seals well. If you have a Saturday morning to do this you can still drive in the afternoon. Don't forget to put the arm back in place on the motor mount. Perhaps the reason the mounts need replacing is because you don't have the support arm.
 

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Discussion Starter #6
Sorted, thank you

Jay, Ian, Don

All done. Thanks for the tips.
And as you said, not too tricky.

Here's some pics for you. (try to ignore the Hylomar I haven't cleaned up yet).

Jay you were right about the support strut (almost). I do have one fitted, but it turns out the silent block at the base had eroded to almost nothing, hence the back two rubber mounts had been moving around far too much, giving me plenty of "pop-bang-and-chuff".

You'll see I selected the Alfaholics aluminium mounts (they have some 102/106 mounts left from a passed special order. Lucky me!
They're fitted with the upgraded rubber grommet mounts too. It's a much more solid set up now, obviously, and I think the O-ring and grommets will keep most of the vibrations at bay. I fixed the support bar silent block too of course.

So far it drives great - mainly because the mixture is now correct. Actually i need to lean it off quite a bit now the leaks have gone, I noticed some black smoke puffs on the test drive.

Next up, rolling road session to tune to the new Pertronix Ignition, new (leak free) mounts and my earlier re-jetting. Should be fun.
 

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Discussion Starter #7
Now fitted
 

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Discussion Starter #9
That'll be the Gunk Spray. Makes everything look new.

Forgot to mention, the Alu mounts are 45's not 40's (despite the DHLA's being 40's)
The manifold was originally made for the PH44 Solex, so it lines up very well, no 'steps' to speak of. The rubber mounts were 40's, so I'm hoping the larger size might help with progression and poss even a little on performance? Fingers crossed.

Will ensure genuine alfa-filth and muck returns to engine bay over time ;)
 

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I am just wondering if the paper gaskets were needed with the 0-rings. Are the flanges the same size on both ends? Thinking mine might be leaking.

Thanks. Dick
 

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Discussion Starter #11
Dick,

Not quite sure I understand, but I'll try to explain the set up I have, it might answer your question...

The Carbs fit onto the mounts on the rubber O ring side and are then bolted on to the mount using rubber grommet and metal spacers between the nut and flange (see above pics). The O ring and the grommets act as both air seal between carb and mount and vibration dampers.

The mounts (with carbs now fitted to them - as in the picture above) are then fitted to the inlet manifold with the 'flat' side of the mount and sealed with Hylomar and paper gaskets. I used the paper gaskets because it's a good way to create a good 'soft' seal rather than just metal-to-metal which can easily leak air. The Hylomar does a good job here too as it wont harden. It stays gooey.

The paper gaskets are only used on the one side of these mounts - the flat side.
The O rings are only fitted on one side of these mount - the 'groove cut' side. (see pics above)

These mounts are specially made to imitate the form of the 102/106 rubber mounts. They are a hybrid of the original rubber mounts and the more conventional O ring spacer set-ups one can buy. As solid aluminium, they shouldn't need replacing ever again.

So far I've noticed no vibration issues either.
Hope that helps?
 

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Very thorough answer! I assumed that both ends used an o-ring. I think the o-ring alone would seal, but that is a matter of untried opinion. The question about size? I asked it, with making a set of these myself without removing the intake first. I guess it would be better to tear down and then fabricate with all of the specs in front of me. I have CNC milling machine so it would be a piece and a half of cake. Will let you know if I do it.

Thanks,

Dick
 

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Discussion Starter #13
The carb and intake flanges of the mounts are the same size. They are rotated to fit left and right hand as the 102 mounts seem to do this - see pics for reference.

They are exactly the same sizing and shape as the rubber mounts.
But obviously 1/4 of the weight and have the seat cut into them to hold the rubber O ring. The studs were slightly longer than the rubber studs.

These are also 45mm chokes not 40mm.

Perhaps Alfaholics will give you the pattern they used for you to mill your own ??
 

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Hi Dick,

If you do decide to make these I may be interested in a set for my 2600. As I am sure you know there is a left and a right mount (not one mount rotated).

John

Pasadena, CA

'63 2600 Spider

[email protected]
 

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John,

Yes, I know there is a left and right configuration, but what does a 2600 use? They do have three carbs don't they?

Does any one know how many degrees (exactly), that the flanges are rotated?

Dick
 

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Each carb requires a left and right set (2 sets for 102 cars, 3 sets for 106 cars).
I don't have the offset information handy.
 

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How dumb of me, too early in the morning for me I guess.

I could measure the angle of the flanges but I am looking for a factory spec. if available.

Thanks, Dick
 

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Discussion Starter #19
I believe Alfaholics (in the UK) may still have some of these 102/106 L/R mounts left from the batch order they did some time back.

Perhaps buying a set (4 mounts) would be worthwhile to get the measurements if you're going to tool up and make a batch for a few people? If they don't have any left, they may well be happy to send you their designs. They're usually very accommodating.

I think they would need an order of around 100 or more to make it worth their while? But got to be worth the question to them.

They charge roughly £140 GBP plus tax and postage (price would include the O rings, nyloc nuts, washers, rubber grommets, spacers etc)
 

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To those with greater experience with Alfas than I, I have a question.

Do any of you have actual experience with running the Solex carbs with a set of solid mounts? Do the original rubber mounts really make them run better? I know a lot of Alfas have been run a bunch of miles without the support rod, which would leave the carbs hanging out in the breeze and bouncing all over the place. That seems almost worse than having them bolted solid to the head. Just wondering.

Thanks, Dick
 
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