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TR2/3/3A another air vent TR3A question

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NutmegCT

NutmegCT

Great Pumpkin
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I just read the previous air vent question. Reminded me that I've got a perplexing situation on my own TR3A air vent.

When I got the car last February, I noticed a small area of rubbing (light scratches) on the scuttle air vent cover.

Soon realized the rubbing is caused by the bottom edge of the bonnet; when the bonnet is raised, the bottom edge actually rubs against the vent cover.

I removed the old, dry rubber gasket under the cover, but even that slight drop in cover height still has the open bonnet touching the cover.

I don't dare put in the *new* gasket I bought, which would raise the cover even higher, and result in even more rubbing and scratching of the paint. Everything seems to fit just fine, but the bonnet seems to be a gazillionth of an inch too far back (?) toward the scuttle.

Has anyone ever had this problem? Any suggestions?

Thanks.
Tom
 
Is there room across the front of your bonnet to adjust it any farther forward? Even a little forward would gain you some clearance along the back edge.

Mine is really close... maybe a 1/16" above the vent lid. In fact, when I hyperextend the bonnet (e.g. for pulling the head) I lay a piece of cereal box cardboard on top of the vent lid to protect it.

I assume you have the stock bonnet prop and are not just using an old broomstick.
 
You must be lifting your hood for the engine compartment too high before you snap the support rod into its rubber thingy.

Either that or some previous owner put on a support rod that is too long.

My hood never comes close to my air vent cover lid. I'm careful not to lift it too high.
 
This is very interesting. Geo_Hahn reports having only 1/16th inch clearing, and using cardboard as a separator to protect the cover. Don says his open hood never comes close to the air vent cover.

The front of my bonnet is already at the maximum forward placement. The spring-held vertical stud on the frame which receives the closing bonnet has to bend backward just to enter the bonnet latch; any farther forward on the bonnet would prevent the stud from sliding into that hole.

My bonnet rear edge touches the vent cover even when the bonnet is resting on support rod - not just when I lift the bonnet to attach the support rod.

One thing I'm going to experiment with today is the physical length of the support rod. Just possible it was replaced at some time in the past, perhaps with a rod that's a bit too long?

Could someone please measure the length of your TR (I assume 2 or 3) bonnet support rod?

Thanks.
Tom
 
I have the same problem with my car. I took the new gasket out of the vent to get it to seat low enough to open the bonnet. I never use my vent because of this.. I try to not run in the rain also...

I think I know the problem with mine... I have a post 60000 car and the bonnet does not have raised hinges and there was some evidence of right front damage repair. I think they changed the bonnet and possibly the front apron with parts from a pre 60000 car. I'm going to make it all correct if I every decide to paint it. It looks great now so there is no big rush for a paint job...
 
Can you slide the hood latch forward a bit. The hood lift that mounts to the apron tie-member is slotted to allow for latch adjustment, fore and aft.

I had the same problem. I adjusted the hood/bonnet forward just a hair and added shims under the hood hinges to raise it up. This gave it just enough to clear the scuttle.

When I have the hood open for service, I put on a layer of blue masking tape on the scuttle to keep from scratching the paint. It's a very close fit.
 
NutmegCT said:
Could someone please measure the length of your TR (I assume 2 or 3) bonnet support rod?
Click to expand...

32.5"

I doubt you have an over-long support but the suggestion to adjust the latch to allow the bonnet to go farther forward is worth looking into.

The limit on how far forward mine can go is the front corners meeting the sheet metal of the apron.

Ah yes, blue masking tape... that's also what I use to cover those 2 vents on the bonnet to keep the engine dry when washing the car.
 
George - When I wash my TR3A, I don't cover those two slots. In fact I wash the car with the bonnet sitting up about 2 inches and right after I have done the outside of the bonnet with my high pressure washer, I lift the bonnet and prop it up with the support rod and spray my 1500 psi spray washer all over the inside of the bonnet as well as all over the engine. This way, I remove all the grease, etc. from the distributor body, valve cover, fuel pump, around the sparkplugs, master cylinder assembly and so on. I do this about 5 times a summer. It always restarts. No plastic bags. No elastics, etc. Only once it wouldn't re-start. The high pressure spray had knocked the high tension cable out the top of my coil. Took only a second to find it and to fix it. Started right up after that.
 
I didn't mean to sound like a wimp who won't get the engine wet... it's just that I use some homemade (color printer) labels on the battery, coil, air cleaner, brake fluid reservoir, etc that will not withstand soaking. So I clean the engine less often and replace the labels when I do.

Sometimes the engine does get very dirty... like when I hit a flooded wash at 50 mph...


muddy%20engine.JPG
 
After 50+ years many things move around, get smashed, bent and otherwise "adjusted". If you figure how many time these cars have been dis-assembled for repairs it's no wonder that parts don't fit properly. The average repair shop in the 1960's would probably have been less concerned about panel fit than those of us hwho own these cars today.

It's my understanding that the sidescreen bodies were pretty much 'hand built' using pre-made stampings and then finished by hand. That leaves a lot of room for error. Anyone who has fitted a used fender to their car may have experienced poor panel fit with the 'replacement fender'...a perfect example of the variations of an early TR.


George...That is a very nice engine compartment. Just seeing the 'Lucas' battery and proper hose clamps makes all the difference in a properly detailed early car.
 
Tom, forgive me if I'm asking the obvious, but:

Are you sticking the prop rod in the right hole? Like in Geo's photo?

I have seen someone stick the prop rod in the Dzus fastener receptacle on the fender, so maybe my question isn't out of line. Tell me if it is.
 
Tom,
The back of my bonnet has caught against the scuttle in the past and chipped the paint off. I notice that the car doesn't have any gaskets under the hinges and I suspect this is not helping. Also my hinges are very worn, causing an embarrassing rattle when the engine is idling, but this will also allow the rear of the bonnet to drop very slightly when opened. I really should replace the hinges with new and put gaskets under them. I guess I would get at least an extra 1/16 inch clearance, which would solve the problem. I also suspect that someone has been sitting on the bonnet (blond babe!) in the past and that it has lost a bit of its curvature. The two rear corners touch the stainless trim on the wings when the bonnet is shut.
Nick
 
Thanks for all the ideas. My goodness, what discoveries I can make when comparing to the TRs of others.

My bonnet (and boot lid) hinges have dark grey cardboard gaskets, looking very much like they were cut with short snips from carb gasket material. Material seems about 1/16th inch thick. I wonder what the proper hinge gasket material (and thickness) are. An increase above 1/16th inch would certainly give more bonnet to body clearance.

Also noticed I've got about 1/8th inch clearance between the front of the bonnet and the apron. I'm afraid that even if the bonnet front were completely flush with the apron, the scuttle, with proper rubber gasket fitted, would still press against the bonnet trailing edge with the bonnet fully opened and supported on the rod. Interesting so many responders mention ill-fits between the scuttle and the bonnet.

John - just to set your mind at ease - the support rod is going down into the proper slot. Also, I measured the support rod, and it matches George's 32.5 inches. Interestingly, with the bonnet raised and supported, the distance from the center top edge of the bonnet to the center rear edge of the apron is also 32.5 inches.

On a side note, despite the car not being fully registered with DMV, I took it for an hour's drive a few days ago with temp plates (before the rains started). Really impressed with the torque and "zip", compared to my former 1976 MGB. What a difference! I never had to downshift for any climbs. Only real negative I discovered was a marked "wobble" or shimmy in the front end at speeds over 45mph (so I never drove over 50). Also did my "shocks" test by bouncing on each corner of the body, and found the rear dampeners quite efficient, but the front end actually wouldn't bounce at all. Strange.

Good news - after the hour's drive in 80F weather, engine never read over center of temp gauge, and there were no "tell tale spots" even an hour after parking over an old white sheet.

I'm getting *very* enamored of this little critter.

Thanks all.
Tom
 
Just a quick follow-up ...

Does anyone know the proper material and thickness for those hinge gaskets?

PeterK: Can you slide the hood latch forward a bit. The hood lift that mounts to the apron tie-member is slotted to allow for latch adjustment, fore and aft.

My latch is all the way forward. But come to think of it, would sliding the latch forward or backward affect the "touch point" at the scuttle I'm having problems with?

Thanks.
Tom
 
NutmegCT said:
Just a quick follow-up ...

Does anyone know the proper material and thickness for those hinge gaskets?

PeterK: Can you slide the hood latch forward a bit. The hood lift that mounts to the apron tie-member is slotted to allow for latch adjustment, fore and aft.

My latch is all the way forward. But come to think of it, would sliding the latch forward or backward affect the "touch point" at the scuttle I'm having problems with?

Thanks.
Tom
Click to expand...

The hood gaskets are listed in the TRF catalog as "shims" and the quantity "As Required." So I would assume that the thickness is to be determined by the need to line things up.
Capt Roy made a good point: his car is later 3A that came with raised hinge mounts but his hood is early with flat hinge mounts; perhaps this mismatch also accounts for your alignment issue.

Sliding the latch won't affect the scuttle but you mentioned yours is already interfering with the ability to slide the bonnet forward. So moving the latch might allow some more forward movement of the bonnet at the hinges. On mine, even a slight tweak diagonally, left to right made a difference at the rear.
 
Peter - thanks for the comment. Indeed, my bonnet has flat hinge mounts - or at least the hinges are mounted without any visible change in "depth" of the bonnet surface.

Noting the commission number of my TR, should it have the flat or the raised mounts? In other words, does it appear I've got a replacement bonnet?

Thanks.
Tom
 
NickMorgan said:
The back of my bonnet has caught against the scuttle in the past and chipped the paint off...
Click to expand...

On mine I had to oval out the holes in the vent hinge just a bit to get it to sit far enough back to not foul the rear edge of a closed bonnet.
 
NutmegCT said:
My bonnet (and boot lid) hinges have dark grey cardboard gaskets, looking very much like they were cut with short snips from carb gasket material...
Click to expand...

If you have them off sometime see if the other side says "ice Krisp" or "rosted Flak".

Cereal box cardboard actually makes a servicable non-critcal gasket though new ones are best made from real gasket material (and will probably fit better than the ready-mades generally available).
 
NutmegCT said:
Peter - thanks for the comment. Indeed, my bonnet has flat hinge mounts - or at least the hinges are mounted without any visible change in "depth" of the bonnet surface.

Noting the commission number of my TR, should it have the flat or the raised mounts? In other words, does it appear I've got a replacement bonnet?

Thanks.
Tom
Click to expand...

According to your commission number, you should have flat hinge mounts on both the hood, scuttle, and the boot (trunk) lid along with the tonneau section back there.

The change occured at TS60,000. Then all of the places where the hinges attach got raised. Apparently they did this to strenghten those areas of the sheet metal.

I could see all kinds of problems developing if you tried to put an early bonnet or trunk lid on a post TS60,000 body shell, or vice-versa. Nothing would line up properly.
 
You can cut your own from a sheet of rubber about 1/16" thick. More if you want more lift. Punch the holes with one of those round cutting hole punches with a hammer against a wooden block. Use a hinge as a model or use the old fiber pad, shim, spacer.
 
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