Important vibrations when first gear

[Flat4ever]

Hello,

I have an important problem of hard vibrations when I start with first gear. The engine make noise BAM BAM BAM BAM BAM and the car is shaken by all parts.

I first thought about clutch but may be engine and/or tranny mounts ?

Do you have any idea ?

Regards.

PS: I tried to start with parking brake, but the engine dropped down, the clutch did not slip.

[John Rogers]

Check the engine and tranny mounts and all related attachment points for broken bolts or welds. Good luck.

Sounds like you broke off a tooth from 1st gear - if it OK in the other gears then 1st is probably broken.

Ken

[Flat4ever]

Originally posted by KenH
Sounds like you broke off a tooth from 1st gear - if it OK in the other gears then 1st is probably broken.

Ken

I do not think to that. I changed tranny oil, there was no metal parts.

[Dave at Pelican Parts]

My car did this exact thing when the motor mounts were sheared off. The whole drivetrain was "winding up" and then slamming back down onto the engine mount bar again. This happened any time I gave it more than a tiny bit of power in 1st gear.

Support the rear of the car securely. Then put a piece of wood on the jack (to act as a pad) and try to lift the motor by the crankcase. If it moves more than a tiny fraction of an inch, you need to replace the motor mounts.

--DD

[Jared at Pelican Parts]

Is the shifter moving at all when you gas it?

This sounds like motor mounts. My car did the same thing when i sheared them. Luckily replacement is relatively easy.

[Flat4ever]

Thanks for answers

I will begin by the beginning: replacing motor mounts. As you can see on pics, there are oil leaks and rubber usually does not love oil.



Driver side




Passenger side

[anthony]

This is a timely topic. My car does this once every 50 starts in first gear. I thought I was going to need a clutch. Motor mounts sounds like a much easier fix.

[bob174]

How do you get in there to remove those things. I couldn't get to them even with the engine out. But I'm not the sharpest tool in the shed either.

[John Rogers]

Replacement of the mounts is much easier if the underside has been steam cleaned very well. Then jack up the rear and put on stands and then support the bottom of the engine with something solid like pieces of 6x6x12 hardwood. Remove the crossbar engine mount and then the mounts and replacement is reverse. There is a bolt at each side of the crossbar and the mount bolts go though it and can be accessed at the bottom. Make sure you use new jam nuts. Good luck.

[Dave at Pelican Parts]

Hint--remove the rear shift rod before you remove the motor mount bar!!

Access to the nuts on the top side of the motor mounts is somewhat difficult. I think I removed my oil filter and some of the heater ducting in order to get my hand up to that area. I used a 1/4" drive "shorty" ratchet, as well. Spin the nuts on as far as you can with your fingertips before going to the socket/ratchet.

I didn't thread the clutch cable back through the small hole in the motor mount bar, I just let the bar dangle with the cable running through it.

--DD

[Flat4ever]

... the bolt !

I just gone to make the test suggested by Dave Darling. I noticed that driver side bolt of the support bar was not as long as the passenger side one.

I thought : "may be it is not torqued ..."

... and it was not. As soon as I tried to screw it, the bolt was turning free, and impossible to torque it.

I put the jack under the bar to support the engine and removed the driver side bar bolt.

Here it is



Impossible to torque, the bar could move and I think it could be the cause of my problems.

I will replace it on Monday and try the car before ordering new motor mounts. Thanks for all folks !

[Dave at Pelican Parts]

Excellent! I would not be at all surprised to find that the bolt is the source of your problems. Ya gotta like it when the problem turns out to be less expensive and easier to fix than you thought.

--DD

[gengs]

This has got to be a seasonal problem, because on Saturday mine started doing exactly the same thing. However it began to happen right after being stuck in very bad traffic on a very steep hill (If you're from London, the hill from Crouch End up to Muswell Hill from Alexander Palace).

My first thoughts were the clutch as it happened on Saturday every time I pulled away in 1st gear, however today it happens once in about 20 1st gears (took it to work today on the M25 the biggest car park in Europe).

So given the posts above can presume that it is the clutch rather than the mounts, or should I presume its the mounts rather than the clutch?

For the record this appears not be the biggest problem at the moment as I noticed on the faster sections of the M25 that every time I applied power in gear the car behind was welcomed with a nice puff of grey / blue smoke. Which sucks as this is new and I've only had the car for a month.

My immediate diagnosis is that I didn't spend very much money on it (1973 2.0) last week and that I need to throw more money at it.

[Dave at Pelican Parts]

Check the motor mounts. It's cheap (FREE!! Free is good, right?) and a lot easier than checking the clutch. Support the back of the car firmly, then jack up on the tranny bell housing. If the motor moves more than just a little bit, it's the motor mounts. You may find, like our Bordeau brother, that the problem is the bolt instead of the rubber mount. (Which is a lot cheaper! )

--DD

[M. Hendrix]

I need a couple sets of mounts.... I think, I remember 914s 20 years ago.. that part of my 914 experience could use a little tweaking..

We have to retro 911 mounts, is that correct Dave-a-mundo?


M

[Dave at Pelican Parts]

I don't think you have to, but you can. They're cheaper than the 914 parts--at least, the "sport mounts" are. A little bit of tweaking of the bolt holes in the body may be required.

--DD

[Flat4ever]

Bad new: It was not the nut/bolt

I just changed it for a new (12.9) one and torqued hard every thing, but there is still BAM BAM BAM and important shaking when starting in first gear.

Let's go to order engine and tranny mounts.

And after, may be the clutch :-/

[Jared at Pelican Parts]

Originally posted by gengs
This has got to be a seasonal problem, because on Saturday mine started doing exactly the same thing. However it began to happen right after being stuck in very bad traffic on a very steep hill (If you're from London, the hill from Crouch End up to Muswell Hill from Alexander Palace).

I know that exact hill. God that would be a nightmare on the clutch.

[Flat4ever]

God that would be a nightmare on the clutch.

Nightmare ? More details ?