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914World.com _ 914World Garage _ Bumper fitment issues

Posted by: mb911 Jun 13 2020, 03:49 PM

I am wondering if its a bumper top, bumper or car? The top is 914 rubber and was bought a year or so ago. The car is not bashed in any wear and the bumper was rechromed by Oscar about a year ago. It fits the same way on both sides starting at the headlights towards the out fender. Again both sides are the same.

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Posted by: 914Sixer Jun 13 2020, 05:59 PM

Bumper top rubber SHOULD lap over the flange under the turn signal bucket. What year car? 75-76 you have to cut off lip off body.

Posted by: Mikey914 Jun 13 2020, 06:31 PM

Do you have the rubber washers installed. If you look at the old bumper they tend to get compressed into the rubber, but they are actually a seporate part.
It changes the geometry by raising it up 1/8".
Could be at least part of the issue.

Posted by: porschetub Jun 13 2020, 06:47 PM

QUOTE(914Sixer @ Jun 14 2020, 11:59 AM) *

Bumper top rubber SHOULD lap over the flange under the turn signal bucket. What year car? 75-76 you have to cut off lip off body.


agree.gif 100%,something odd ? is a delete "dog bone " mod needed here...just saying ?.

Posted by: mb911 Jun 13 2020, 07:42 PM

QUOTE(porschetub @ Jun 13 2020, 04:47 PM) *

QUOTE(914Sixer @ Jun 14 2020, 11:59 AM) *

Bumper top rubber SHOULD lap over the flange under the turn signal bucket. What year car? 75-76 you have to cut off lip off body.


agree.gif 100%,something odd ? is a delete "dog bone " mod needed here...just saying ?.

Its a 73 .. I did add the rubber washers.

Posted by: gereed75 Jun 13 2020, 07:52 PM

The metal insert that goes into the dog bone hole is about 3/16 longer than the dog bone is thick. This extra length fits into the bolt through hole. If it is not positioned in the hole it will hold the bumper out at the top

Sounds obvious but you have to hold the weight of the bumper up while tightening bolts or they will bind, feeling tight but not really. I used bar clamps to hold the bumper up last time I did it

Posted by: mb911 Jun 14 2020, 05:56 AM

QUOTE(gereed75 @ Jun 13 2020, 05:52 PM) *

The metal insert that goes into the dog bone hole is about 3/16 longer than the dog bone is thick. This extra length fits into the bolt through hole. If it is not positioned in the hole it will hold the bumper out at the top

Sounds obvious but you have to hold the weight of the bumper up while tightening bolts or they will bind, feeling tight but not really. I used bar clamps to hold the bumper up last time I did it



I actually always wondered why the metal inserts were even in there.. Thought they were kind of silly.. I will try that. Thanks..

Posted by: gereed75 Jun 14 2020, 06:52 AM

Hope that does it Ben. Might want to chase the captive nut threads (M8 x .8 IIRC) and apply a bit of anti seize.

Just changed my bumpers and several of the threads were bunged up. I think it is the unsupported weight of the hanging bumper while wrenching that does it.

Posted by: Olympic 914 Jun 14 2020, 09:17 AM

Using allthread instead of the bolts makes the installation easier. Then if you like you can remove the allthread one at a time and replace the bolts. cutting a screwdriver slot in the end of the allthread helps when removing them.

My car had work done in the bumper mount area on both sides so I had to adjust the rubber dogbone thickness to get the fit right.


Posted by: mb911 Jun 14 2020, 10:18 AM

QUOTE(Olympic 914 @ Jun 14 2020, 07:17 AM) *

Using allthread instead of the bolts makes the installation easier. Then if you like you can remove the allthread one at a time and replace the bolts. cutting a screwdriver slot in the end of the allthread helps when removing them.

My car had work done in the bumper mount area on both sides so I had to adjust the rubber dogbone thickness to get the fit right.



Another good idea


Posted by: gereed75 Jun 14 2020, 11:49 AM

That might work. You could jam nut the all thread in against the captive nut to make a “removable stud”. Just leave it in there

Posted by: 914e Jun 14 2020, 12:01 PM

QUOTE(Olympic 914 @ Jun 14 2020, 08:17 AM) *

Using allthread instead of the bolts makes the installation easier. Then if you like you can remove the allthread one at a time and replace the bolts. cutting a screwdriver slot in the end of the allthread helps when removing them.

My car had work done in the bumper mount area on both sides so I had to adjust the rubber dogbone thickness to get the fit right.


Where did you find the metric threaded rod? It is hard to find in the US.
Most common allthread is grade 2, so I would definitely replace it with the bolts after you have it installed.

Posted by: Mark Henry Jun 14 2020, 01:06 PM

Do you have the rubber pads installed on the inner mounts?
Try taking them off.

Hate to mention this but... steel can warp when being chromed, so check the curvature of the bumper. If they fit better without the rubber pad they are likely warped, in this case the curve would have flattened out a bit.

Posted by: Mark Henry Jun 14 2020, 01:56 PM

Another idea is to slot the bumper topper mounting holes, so you have more adjustment on the rubber topper.
I know it's a bit of a hack and looks like crap but once the topper is on you can't see it.

How does just the bumper fit? What's the body lines like at the fenders?
Too me it looks way out. Is it the bumper or the topper that's off? Or are they both off?

Posted by: sixnotfour Jun 14 2020, 02:37 PM

UhOh….
http://www.914world.com/bbs2/index.php?showtopic=310073


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Posted by: Mark Henry Jun 14 2020, 03:03 PM

If like above, it looks to me like the whole bumper is tilted forward at the top. You could cut the mounts and see if you can make them fit.


This is just one of the reasons why I abandoned the stainless steel bumper GB, final fitting. The Vietnam bumpers were not that far off but it took me 8+ hours to fit one front bumper.

Posted by: mepstein Jun 14 2020, 03:08 PM

QUOTE(914e @ Jun 14 2020, 02:01 PM) *

QUOTE(Olympic 914 @ Jun 14 2020, 08:17 AM) *

Using allthread instead of the bolts makes the installation easier. Then if you like you can remove the allthread one at a time and replace the bolts. cutting a screwdriver slot in the end of the allthread helps when removing them.

My car had work done in the bumper mount area on both sides so I had to adjust the rubber dogbone thickness to get the fit right.


Where did you find the metric threaded rod? It is hard to find in the US.
Most common allthread is grade 2, so I would definitely replace it with the bolts after you have it installed.

Buy a metric threaded stud. Pretty common.

Posted by: bkrantz Jun 23 2020, 09:23 PM

How many people shaved some thickness off the dog bones to bring the bumper closer?

Posted by: mb911 Jun 23 2020, 09:29 PM

QUOTE(bkrantz @ Jun 23 2020, 07:23 PM) *

How many people shaved some thickness off the dog bones to bring the bumper closer?



I removed the steel inserts on the last car I had so I could squeeze tighter.. Worked well.. I removed 3/16" from these.. Should work just fine.. I have it pretty close now.

Posted by: roblav1 Jun 23 2020, 10:06 PM

I got lucky a couple weeks ago. Original bumper and top fit fine and took about 10 minutes to install.


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Posted by: JOEPROPER Jun 24 2020, 06:40 AM

QUOTE(mb911 @ Jun 23 2020, 11:29 PM) *

QUOTE(bkrantz @ Jun 23 2020, 07:23 PM) *

How many people shaved some thickness off the dog bones to bring the bumper closer?



I removed the steel inserts on the last car I had so I could squeeze tighter.. Worked well.. I removed 3/16" from these.. Should work just fine.. I have it pretty close now.

Ben, do you have a picture if it now? I have a similar issue.

Posted by: mb911 Jun 24 2020, 06:44 AM

QUOTE(JOEPROPER @ Jun 24 2020, 04:40 AM) *

QUOTE(mb911 @ Jun 23 2020, 11:29 PM) *

QUOTE(bkrantz @ Jun 23 2020, 07:23 PM) *

How many people shaved some thickness off the dog bones to bring the bumper closer?



I removed the steel inserts on the last car I had so I could squeeze tighter.. Worked well.. I removed 3/16" from these.. Should work just fine.. I have it pretty close now.

Ben, do you have a picture if it now? I have a similar issue.



No took it off now to start body work on the front fenders..

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