12 replies to this topic

[mvahora]

Have jacked up the car and found the following issues on the rear subframe:

 

1. A head on one of the bolts that holds the trunnion onto the heel-board was cracked off. So the subframe has been bolted on with only 3 screws into the heel board rather then the 4 this entire time. The other 3 are okay. I carefully and slowly managed to get them out without any of them shearing off. I managed to then remove the subframe by spraying a load of penetrating spray and gently wedging between the heel board and subframe allowing the trunnion to slide of the sheared bolt. 

 

2. A Bolt on the Left radius arm bracket is missing. Only held on by 3. 

 

3. A Bolt on the Right radius arm bracket is loose/spinning as the captive nut in behind is cracked off.  

 

What is the best way to sort these issues out?

 

Will post some pics soon

[wile e coyote]

Sounds like a poor effort on previous subframe replacement - the great thing is that you've obviously got a solid heelboard to work with with captive nuts ok  that's 99% of the battle won - I've previously bought a car in a worse  state with an mot - had all four of the front trunnion bolt heads sheared - I drove it 200 miles home in that state....iMHO the subframe fixings are over engineered - thats not to say you shouldn't fix it though - I'd just replace the missing bolt and refix the captive nut that's spinning on you with a couple of tack welds....

Edited by wile e coyote, 27 December 2021 - 10:11 AM.

[mvahora]

missing bolt and the top of the subframe condition

Attached Files

•  20211227_173307_HDR.jpg   40.25K   6 downloads
•  20211227_150008_HDR.jpg   66.27K   9 downloads

Edited by mvahora, 27 December 2021 - 11:49 AM.

[mvahora]

subframe condition and the bolt spinning due to cracked captive nut

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•  20211227_151136_HDR.jpg   45.12K   2 downloads
•  20211227_173303_HDR.jpg   44.42K   3 downloads

Edited by mvahora, 27 December 2021 - 11:49 AM.

[mvahora]

condition of removed bolts and the existing sheared bolt stuck in trunnion

Attached Files

•  20211226_203644_HDR.jpg   22.22K   4 downloads
•  20211226_200153_HDR.jpg   28.19K   3 downloads
•  20211226_200144_HDR.jpg   32.62K   1 downloads

Edited by mvahora, 27 December 2021 - 11:48 AM.

[62S]

For 1 - the sheared bolt - if you have access to welding gear screw a nut on to the remaining thread and tack weld it on, the heat from welding this should be enough to break the rust seal and allow you to wind it out easily enough. If no welding gear, plenty of heat from a blowtorch on the remains of the bolt and it should screw out fairly easily with Mole grips or the like. If you are going to use heat, remove all of the interior trim from that area

 

For 2 - the missing bolt - you could drill and tap to the next size up if the captive nut is still attached

 

For 3 - the spinning bolt - if it is the inner bolt of the two you should be able to get a spanner on the broken off captive. Plenty of heat from a good blowtorch will work wonders. There is nothing particularly special about the captive nut - you could simply weld it back on or just use another nut of the correct size

[mvahora]

Sounds like a poor effort on previous subframe replacement - the great thing is that you've obviously got a solid heelboard to work with with captive nuts ok  that's 99% of the battle won - I've previously bought a car in a worse  state with an mot - had all four of the front trunnion bolt heads sheared - I drove it 200 miles home in that state....iMHO the subframe fixings are over engineered - thats not to say you shouldn't fix it though - I'd just replace the missing bolt and refix the captive nut that's spinning on you with a couple of tack welds....

 

Yup im glad the captive nuts in the heelboard are okay. In regards to the bolt that has the head sheared off in the heel board; would it be okay if I rewelded a new head onto it once its sitting back on the trunnion? im worried if I heat it up and then try remove it it might somehow crack the captive nut on the back. Then id have a bigger headache.

 

In regards to the loose captive nut and bolt spinning on the radius arm bracket, does the nut have to be welded on to the subframe? why cant I just put in a new bolt and nut and tighten them without welding the nut to the radius arm bracket on the subframe? 

Edited by mvahora, 29 December 2021 - 12:55 AM.

[mvahora]

For 1 - the sheared bolt - if you have access to welding gear screw a nut on to the remaining thread and tack weld it on, the heat from welding this should be enough to break the rust seal and allow you to wind it out easily enough. If no welding gear, plenty of heat from a blowtorch on the remains of the bolt and it should screw out fairly easily with Mole grips or the like. If you are going to use heat, remove all of the interior trim from that area

 

For 2 - the missing bolt - you could drill and tap to the next size up if the captive nut is still attached

 

For 3 - the spinning bolt - if it is the inner bolt of the two you should be able to get a spanner on the broken off captive. Plenty of heat from a good blowtorch will work wonders. There is nothing particularly special about the captive nut - you could simply weld it back on or just use another nut of the correct size

 

Thanks for that. see my reply to wile e coyote above. Suggestions? (I tried replying you both as a multi quote but it didnt let me lol)

[62S]

Plenty of heat really is your friend when it comes to rusty nuts/bolts - you will probably be surprised how easily the rustiest looking of things come apart if you have not tried it before. An application of proper releasing fluid such as Plus Gas or Molytec will also help - ideally apply a day or more before trying to disassemble.

 

No real reason why you can't use a nut and bolt for the radius arm bracket, just make sure you use a good quality spring washer as well as you don't want it coming loose.

[mvahora]

Plenty of heat really is your friend when it comes to rusty nuts/bolts - you will probably be surprised how easily the rustiest looking of things come apart if you have not tried it before. An application of proper releasing fluid such as Plus Gas or Molytec will also help - ideally apply a day or more before trying to disassemble.

 

No real reason why you can't use a nut and bolt for the radius arm bracket, just make sure you use a good quality spring washer as well as you don't want it coming loose.

 

Hi, 

 

So I placed a nut onto the broken bolt and filled it with weld. Got it glowing hot! Put a ring spanner on it and she came out easy The screw was very small and had corroded away almost entirely! I also noticed that this particular corner is rusting so now ill need to fix that up. Any recommendations on how i can repair the rust. (pic below)

 

I also ended up welding the broken captive nut back onto the subframe. Not the best of jobs but its my first time using a welder! 

Edited by mvahora, 13 January 2022 - 06:39 AM.

[mvahora]

surface rust in boot. this shouldnt be too bad to tidy up.

 

The bad rust is behind the arch flare. Its rusting from next to the trunnion mounting location on the heelboard (as can be seen in the pic) through the side of the sill outwards which is covered by the flare. I moved the flare away and i can feel it bubbly and soft there. 

Attached Files

•  20220113_185801_HDR.jpg   38.58K   5 downloads
•  20220113_185820_HDR.jpg   28.91K   4 downloads
•  20220113_185853_HDR.jpg   45.4K   5 downloads

Edited by mvahora, 13 January 2022 - 06:56 AM.

[cal844]

Needs lower quarter repair panel, also check the heel board ends and the other side rear quarter for the same damage.

[sonscar]

With some dexterity you can replace this from the companion bin and underneath.It is some next to useless double skinned bit.Steve..