Sumo Air Intake + Oval filter + lifter plate = a little prob

[Dan]

Thought I'd better highlight an issue to current Sumo builders.

Last night I trial fitted the bonnet on the car to find that the bonnet rested at about it's center on the Oval 'Cobra' air filter I have (Like the one fitted to Bob's Cob). The last time I had trial fitted the bonnet I didn't have any problem with the airfilter.

I had however fitted a carb leveling wedge since the last trial, which raised the front of the air filter is by 2" to 3" which now fowls against the bonnet.

I now have 3 options:

1) Remove the leveling plate (And have the carb not level)

2) Replace the filter with a round item (And lose the styling)

3) Get out the angle grinder and fibreglass and modify the bonnet.

As I'm fairly confident with fibreglass (I have to repair the bike at regular intervals) I will probably opt for the 3rd option and extend the intake nose by 6" or so. The only real problem is that the bonnet is double skinned - but where there is a will...

Whilst on the subject of bonnets - I have noticed that the Sumo bonnet is Bowed - what I mean by this is that when the bonnet is fitted it lies flush to the bottom and top but half way up it can be 8mm or so out. The body can be pushed up to and supported from underneath to take this out but it's another adjustment that needs to be made... I had a look around at the Detling show and the couple of Sumo's I spotted both had 'Bowed' bonnets... Is this a recent issue or do people with older cars have the same symptoms?...

One last thing. Does any body have any handy tips/tricks for getting the bonnet latches fitted in the correct place?...


Dan 'Were all these nuts used before' Man
www.cobra.kitcar.btinternet.co.uk

[Paul B]

With regard to the "bowed" bonnet, I found that the front lower body mounting, beneath the radiator, needed trimming slightly to allow it to be pushed back toward the radiator. This causes the body to flex very slightly and improve the bonnet to body alignment. Obviously, don't trim too far or you will create high stresses within the body that can lead to small cracks appearing !!

The bonnet latch alignment is simple - be very very very careful!

I looked at engaging the latches through the bulkhead but felt that to get close enough to the bulkhead resulted in the latch handles being very close to the edge of the bonnet. This could make the area weak.

In the end I made two 90 degree brackets sticking out about 25mm, that I bolted to the bulkhead and carefully measured and drilled for the latch handles. The latches then engage under the brackets. So far this has caused no problems.

[Dan]

Glad you mentioned the chassis front member - prompted me to ask another question... Do you have the nose of your body fitted on top of or suspended under neath of the front chassis member?

On my car it natrally sits under the chassis. If I force the front of the body on top of the chassis member the radiator fowls the sides...


Dan 'Were all these nuts used before' Man
www.cobra.kitcar.btinternet.co.uk

[Dan]

My radiator is fitted towards the back of the front member and the fixings actually lift it up by 1/2" - plenty of room for the body tub to slide underneath. The problem is that the bottom corners of the rad rub against the bottom of the tub where it begins to curve upwards.

I'm sure given a bit of time in a spot lighten room I could persuade the nose of the body over the raidiator. However - if the rad was 1/2" higher then it would be alot easier... I fitted the rad low to allow enough clearance between the top of the rad and tub - I have masses of room on the top (2" or so).


Dan 'Were all these nuts used before' Man
www.cobra.kitcar.btinternet.co.uk

[breskit]

That explains the problem. Your rad is located in the wrong position. Is it the Sierra 2.3D rad? If so, trust me, move it to where my orinial diagram shows. You will have plenty of room - I have just recently done this with mine. I had to move it otherwise the thing would just not fit. Just needed to replumb it after it was moved.

[mikey]

How deep is your levelling plate. I initially had this problem but only by about 5 mm. I had the plate skimmed taking the narrow end down to a couple of mm. Also slight angle forward is not a problem on the carb as long as its not severe, some racers use this to overcome fuel surge. The reduced depth of spacer does not incur warping or so I have found as I have experienced no problems in 5 years of running.
Hope you get it sorted.
Mike.

[Dan]

I have found that moving the front nose so it is on top of the front member has helped to raise the front of the bonnet (as the Sumo bonnet hinge is attached to the body tub) which has helped. I could possibly get the plate skimmed but I don't believe enough of an alteration can be made to get it to fit. It's a shame but I believe the best thing for my snake is to have a face drop

Dan 'Were all these nuts used before' Man
www.cobra.kitcar.btinternet.co.uk

[breskit]

Dan,

I had the same problem as you with regard to the front on the body fouling with the radiator. Question is, where have you fixed your radiator to the chassis?

I can tell you that the body should be fitted to the top of this member, not underneath.

I ended up having to move my radiator as it was fitted on the front chassis member, the brackets of the radiator seemed to suggest it fitted there. It actually need to fit on the rear of the front member meaning that the radiator brackets need trimming first. This helps avoid problems where the top of the radiator interferes with the top of the body.

The picture below shows the problem I was having. I'll send you another pic later if you want it showing how it is fitted now.

[breskit]

Dan

What rad do you have? I assume it's a Sierra 2.3Diesel.

Forgive the crude drawing below, but this shows the front chassis member (black), where the body fits (red) and where the rad should be located (blue).

The front member acutally has two "platforms" and the rad should be fitted to the higher of the two (is this where your's is located). If so, I can't see how the rad is rubbing against the body.

Tony B

[Dan]

I have modified your image to show where I have located my Rad...

I believe it is where the oil cooler is normally fitted - but because the oil cooler isn't as long it's not such an issue

Dan 'Were all these nuts used before' Man
www.cobra.kitcar.btinternet.co.uk