Carb rubber things

[Monkeyzak]

Hi.

My car was running rough yesterday. I noticed the rubber Square things the carbs are attached to are split on one of the carbs. Do these serve a purpose?

Can I fill the splits with silicon stuff as I want to keep the car on the road this year and do it over the winter? Or do they need fixed now?

[Howard_B]

The modern replacements are poor quality and have a reputation for failing after a very short period.

If you can't get NOS or decent second hand ones, a short term fix is heavy duty cable ties to support the carbs and take the weight off the rubber. There are a couple of longer term repairs - S&S - are advertising metal replacements & the one of the Dolomite clubs also have their own version.

H

[saabfast]

As a temporary measure silicon with the cable ties added to pull it together might work for a while. If you fit any type of rubber replacement it is a good idea to fit the cable ties as it takes some of the load off the rubber and helps prevent early failure.

[Hasbeen]

Sikaflex [urethane compound] will do a much better patch up job than silicone.

Hasbeen

[Beans]

This has been discussed extensively in the past, use the search function or look in my weblog, label SU ...

[Monkeyzak]

Does the split affect the running? Will do some searches and check your blog

[saabfast]

Yes, it will be sucking air in there weakening the mixture. Probably pretty rough running and if too weak does not do the engine any good. If its not like that the cracks may not be right through yet, seal and add the zip ties and they might last a bit longer.

[Beans]

You could use something like Startpilot sprayed over the mounts with the engine running to check if they are leaking.
If there is a leak the revs should increase when you spray on the top of the mounts.

[UKPhilTR7]

All of the after market ones that I have brought in the past have not lasted very long at all. As said before S&S are selling some metal replacement ones, that I will be looking into getting a little bit later as a long term replacement. Cost a bit, but if they do the job and last it will be worth it.

For now though with my poor quality aftermarket ones, I totally agree with the comments about the cable ties either to fix now and to keep safe after you get some new ones. I brought a new pair a few years ago and fitted them all OK. I then took the car to a local garage for some work. When I got her back I noticed she was running rough. After a look around I noticed that the rubber carb mounts were split. I can only assume that a guy at the garage had lent on the carbs which had resulted in the mounts splitting. So as you can see in the pic below, I always have a pair of cable ties fitted to protect my mounts from mechanics/people who should know better. Also it allows me to move around the engine bay without the fear of splitting the mounts myself.

[FI Spyder]

On our 3,000+ miles club trip to California in 2011, the other TR7's carb mounts split on our first morning after lay over. It wouldn't start (even when pushed by an MGB ( )). The air box was taken off after most of the morning was spent trying to diagnose the problem where it would start but run rough. Carb movement was noticed and my brain clicked in as I hit may forehead with palm and told them to zip tie them up. That worked for the rest of three week trip. Having the carbs unsupported while hanging out is not a good design. The FI air plenum is supported by two stays from the bottom, one mounted at the bottom at the (no longer there) mechanical fuel pump area. Something similar could/should be done if you have an electric fuel pump or some more elegant solution than zip ties from above.

[Beans]

... or some more elegant solution than zip ties from above.

That's where the alloy mounts come into view
More reading in this thread ...
http://tr7triumph.com/forum/viewtopic.php?f=3&t=23684&p=241048

[sonscar]

My carb car has a rubber Mount under the air box.I did away with the cable ties and went heavy duty with worm drive clips,not so elegant.Steve

[Monkeyzak]

Phoned about the alloy mounts. About £120 plus postage so not cheap.

I'm trying to spend as little money on the car as i can now as I'm in for a bit. I want to keep driving it and list all the things I'll tackle over winter

I've sealed them with that sycoseal that was recommended (forgot its name) andll cable tie them. Hopefully I'll get a few months out of them

I like the car. If i decide to keep it I'll do a load over the winter

[UKPhilTR7]

At least you have sorted something out for the moment that is the main thing. Don’t forget that you do not have to spend 120 pounds on fancy alloy ones. You can buy the aftermarket rubber ones from places like rimmer, robsport or s&s for about 15 pounds each and then cable tie them up (like in my picture) to secure them. That will keep them safe for a fair few years. Mine have been on for 7 years now like that without any issues. Yes the alloy ones are long term, but if you don’t want to spend that kind of money there are options.

The sheer fact that you like the car should be one of the main factors on keeping the car. Also you have learnt a fair bit about them now and found such a wealth of information here, which should drive your decision to keep her. If not though, I am sure you could sell her here. However, do not think for one minute that if you do your list of jobs over the winter that will be it for good. If you keep her you have got to realise that you will be spending both time on money on her. That is just the nature of our quality build British Laylend cars lol. I have had mine for 13 years now and I am continually working and spending on her as that is what I love to do. Not saying that the wife loves me doing it, but I do

[Steve @ SandS]

You can't buy the cheap rubber ones from us because I will not sell them because they are crap. The only ones I will sell are our new alloy ones or good used original which are getting harder to find. Tie wrapping them is a good "get you home" fix but isn't something that should be used long term.