Bonnet Latch Problem

[John Vardanian]

I have a problem with my bonnet and I am thinking it is inherent to this type of latch. The problem is I close the bonnet, gaps are good, but once the car goes shaking down the road the right edge of the bonnet creeps up slightly. I wondered if anyone else with this kind of a latch experiences the problem of the hood moving about to the right. Thanks.

john

[DWR46]

John: Does the right side of the hood raise up, or does it move sideways? If the problem is in the hood raising on one side, you can play with the height of the hood rubber bumpers by shimming them to get the hood to be very solid when it is closed and that should stop the movement.

[John Vardanian]

Hi Dyke, actually, it's more like it scoots sideways. The below picture shows what I mean. I have adjusted the latch for maximum tension, played with the black bumpers and even carved and fixed a wine cork in the right side of the hood gap to no avail.

In the above picture, see that piece that looks like a lobster claw, when the hood slams shut, the pin that is in the hood itself goes in the middle of this "claw" and clicks it in a near horizontal position--facing toward the right side. Now, my thinking is that the claw, by design cannot locate the hood in an absolutely fixed position--unlike the Elena/Boano, or the later Lusso designs. So to rule out a faulty latch I thought I would ask others with similar latches.

john

[tyang]

Hi John,

The 250GTEs have the same hood latch.

If the right edge creeps up slightly, do you have enough tension on the left edge from the bumper? You may have to lower the latch height to give the hood enough tension to give even heights from right to left. I know you said you played with this, but I'm just asking.

Tom

[John Vardanian]

Hi Tom, thanks, yes, the latch box is adjusted to its lowest point which means maximum tension on the pin.

john

[250GT]

Hi Dyke, actually, it's more like it scoots sideways. The below picture shows what I mean. I have adjusted the latch for maximum tension, played with the black bumpers and even carved and fixed a wine cork in the right side of the hood gap to no avail.

In the above picture, see that piece that looks like a lobster claw, when the hood slams shut, the pin that is in the hood itself goes in the middle of this "claw" and clicks it in a near horizontal position--facing toward the right side. Now, my thinking is that the claw, by design cannot locate the hood in an absolutely fixed position--unlike the Elena/Boano, or the later Lusso designs. So to rule out a faulty latch I thought I would ask others with similar latches.

john

Hello John,
before you trace a new or replacement of the catch system I looked in my poor stock
the clawposision are half past 6 (releaved) to quarter past 3 (fix) to the right.
But I cpould inmage that the springs (2) on the inside have been broken or lost springstrenght,
due to the way how often you maintain you're cars !( little joke)
see pics below

best
C.


For those are interested in text on back plate of the claw:

Schonitzer
BREV 461852
464595
S.A.F.E

[John Vardanian]

Hi Cornelis, thanks as always for being so helpful with pictures. I really do not think mine is broken, but I will remove it to inspect and will report the findings in a few days.

john

[kare]

Looking at my pictures PF Coupes have 8 rubber sutds - 3 on each side and 2 in rear of bonnet. On GTE there are 10, with 4 studs on rear edge . This might indicate that a problem was discovered when these cars were in production and they tried to solve it by adding more studs.

A few suggestions:

If your rubber studs have gone out of form and hardened, they might not bind the bonnet as they are supposed to. A bag of 10 costs around 50 euros in Italy. Rutlands seems to list them on ebay ($79 for 8, $99 for 10).

If they are not all adjusted to make proper pressure against the bonnet, it might be there is not enough friction to keep the bonnet in place. On my GTE great care had been taken when adjusting the rubber studs. Some had pieces of 2mm or 3mm rubber sheet place under them to raise them. Are you sure all of yours have been properly adjusted?

If they are properly adjusted there might still not be enough friction.

My car has a u-trim around the spot welded ridge running around engine compartment. It clearly supports the stud from one side so they cannot deform to that direction. Most PFs I've seen don't have one.

You might think of adding two studs extra studs to get more grip. Concours judgs will all faint, off course, but adding two studs close to the lock might really solve the problem.

Best wishes, Kare

[John Vardanian]

Thanks Kare, will try the rubber studs next, since I confirmed the latch mechanism seems to look and work fine.

john

[kare]

Only now I came to think that I've also seen cars with a "V" welded on top of the lock and a matching pin into the bonnet. Always wondered what was going on, but obviously previous owners have experienced the same problem!

[John Vardanian]

Hi Kare, I'm not following you, pls explain.

john

[kare]

I remember seeing some cars with a V-shaped steel piece grafted onto the lock and an additional pin welded into the matching piece on bonnet, so when the lid is closed and the pin falls into the "V", the bonnet is centered and held in place by the installation. A clear indication of other people having experienced same type of problem you are!

[John Vardanian]

Hi Kare, yes, exactly. Once the bonnet is shut the "V" is turns to the side like this ">", which is why the bonnet has some freedom to scoot one way and not the other.

See that semi circlt hat is notched in one side of the "V", what if one were to use a round file to make that simicircle deeper?

john

[kare]

No, no I mean I've seen another "V" - a solid one added to the installation with another pin, so in the end there we ">V" and two pins.

I would not file the lock. It likely won't work and then you have a modified lock evetually with more problems.

But wait a minute, on (late) GTE's there is also a slider, similar as on doors, which is supposed to keep the bonnet from moving to passenger side. So the PF Coupe does not have one? The slider is supposed to meet the driver side end of the lock body, I think.

[John Vardanian]

Hi Kare, by slider do you mean the little tab to the side of the pin? My car has one (like this pic I found on the net) but as you can tell by looking at the latch box, it is ballast and doesn't reciprocate with anything on the latch box. It looks like Pininfarina used a door latch on the hood.

BTW, you said "V" and ">". What is that? Can you show me a pic?




john