engine bolts - high tensile? - Page 3

JSP · 07 March 2009, 15:35

Pulled this thread up from a search on what bolts.

Sadly most of the links don't work anymore.
My engine bolts go through the bracket, transom and then through a peice of steel box section (1 going across the top two bolts and one across the bottom 2).
I want to do away with the 2 pieces of box section and instead fit thick Stain less steel plates to spread the load on each nut. But this will leave me with 4 very long bolts sticking out of the transom waiting to make someone bleed.

(get on with it!!)

So where do I buy 4 nuts and bolts from that (?) isn't going to course a " Your not spending more money on that boat!!" argument with the witch in doors.

PeterM · 07 March 2009, 15:40

Can I assume the bolts stick into the boat ( hence possibly draw blood) ? If this is the case can you just turn them round so they stick 'out' of the boat ?

JSP · 07 March 2009, 15:49

Ah but they're so long I wouldn't like them sticking out the back either. They are going from going through, say, a 2 inch box section to going through a 5mm S/S plate.
Not sure if this is right but have always been told to replace a torqued up bolt and nut for a shiny one?

PeterM · 07 March 2009, 15:53

I will admit I would be very very tempted to take a hacksaw to them ( carefully)- leave the nuts on to clean up the thread & hey presto shorter bolts ! I cant think they would fail if they are any good and are 'probably' well within any margin of safety before they fail.

JSP · 07 March 2009, 15:59

Quote:

Originally Posted by Blackroady

I will admit I would be very very tempted to take a hacksaw to them ( carefully)- leave the nuts on to clean up the thread & hey presto shorter bolts ! I cant think they would fail if they are any good and are 'probably' well within any margin of safety before they fail.

It's an idea mate! Wonder if I could get a plate with a cut out so I can just slide them over the bolt and tighten the but up. That way I don't even have to unscrew the fecker

codprawn · 07 March 2009, 16:20

http://www.namrick.co.uk/browse.asp?PCID=5

These are pretty cheap!!!

There is nothing wrong with cutting off the bolts and running a die down them afterwards if you know what you are doing.

JSP · 07 March 2009, 16:32

I'm tempted by the idea of cutting the box section out from around the back of the nut. Then cut a section out of the S/S washer to the centre hole. (LINK)
Then over lap two washers, one sliding over the top of the bolt and one sliding up from the bottom and torque the nut up onto these. Then cut the excess bolt off.
What do ya think? Shite or right?

Sorry should say that doing the above with out taking the nut off.

bedajim · 07 March 2009, 17:26

Quote:

Originally Posted by JSP

Not sure if this is right but have always been told to replace a torqued up bolt and nut for a shiny one?

Do you fit new nuts to hold your wheels on everytime you have new tyres

JSP · 07 March 2009, 17:27

Quote:

Originally Posted by bedajim

Do you fit new nuts to hold your wheels on everytime you have new tyres

True but wheel nuts aren't torqued up though

martini · 07 March 2009, 17:39

Quote:

Originally Posted by JSP

True but wheel nuts aren't torqued up though

Supposed to be!

Theres a very good chance that you've got bolts instead of set screws which means the thread wont be long enough after you take the box section out so you'll have to buy new bolts anyway.

Don't worry about all these fancy, overpriced high tensile jobbies, just get some new stainless ones in those marine pre-packs

JSP · 07 March 2009, 17:44

Quote:

Originally Posted by martini

Supposed to be!

Theres a very good chance that you've got bolts instead of set screws which means the thread wont be long enough after you take the box section out so you'll have to buy new bolts anyway.

Don't worry about all these fancy, overpriced high tensile jobbies, just get some new stainless ones in those marine pre-packs

I've always gone by the rule of tightening the wheel nuts up as tight as you can get them and then put your foot on the bar for an extra crunch. Torque in them up will leave you in a spot at the side of the road.

Anyway, I never thought about that Martini!

For some reason I thought it would be threaded at least half to a third of the way down. D'OH!!!

martini · 07 March 2009, 17:51

Lets hope the mrs doesnt get a puncture in your car then! Wheel nut torque is normally 70-80 ft/lb which isn't that tight at all, would probably suprise you!

codprawn · 07 March 2009, 17:56

It's different with alloy and steel wheels. Especially old Land Rovers!!! You need to torque up the alloy ones but it's just not tight enough for the steel.

Remember lot's of things specify tigthening to a certain torque and then an extra 1/16th of a turn or whatever. That is exactly the same as nipping it up a bit!!!

JSP · 07 March 2009, 18:01

Quote:

Originally Posted by JSP

Not sure if this is right but have always been told to replace a torqued up bolt and nut for a shiny one?

Ok will re phrase what I said as by torque I mean TORQUED.

Not sure if this is right but have always been told to replace a highly torqued up bolt and not for a new one.

codprawn · 07 March 2009, 18:17

Depends on how tight I suppose. Some cars use stretch bolts on the cylinder heads and they do need to be replaced after a certain number of cycles.

On a similar point I remember seeing how they tighten some huge bolts in the Port Talbot steel works. They stretch the bolts first - screw the nuts on hand tight and then release the bolts - they contract back to their original length and you have very tight nuts............

JSP · 07 March 2009, 18:20

Quote:

Originally Posted by codprawn

They stretch the bolts first - screw the nuts on hand tight and then release the bolts - they contract back to their original length and you have very tight nuts............

Once had a girl do that to me

She was all teeth too.

I'm hoping the bolts have enough thread to get back to the transom but thinking about it, I doubt it as Martini says.

Right, back to what nut and bolt to buy?

PeterM · 28 April 2010, 22:26

Having searched this thread seems to be the best on moutning bolts.

I went this evening to fit the bar that spreads the load on the top mounting bolts only to realise the bolts aren't long enough to go through the washer , bar, transom, engine , washer and on to the nut !

So I need new bolts - ideally very very quickly so I can get bolted up properly for the weekend. I'll be on the phone at 8 to chase up but any known stockists ?

Anyone know of anywhere around that may carry them off the shelf ( in the Bournemouth area - or Portsmouth as I can head that way on Friday)

Dirk Diggler · 29 April 2010, 09:18

What length do you need?

PeterM · 29 April 2010, 11:10

Quote:

Originally Posted by Dirk Diggler

What length do you need?

Have to be about 14 cm in all, with maybe 8 cm shoulder.

Dirk Diggler · 29 April 2010, 11:31

Give Gareth at Marinautic a call, he'll have those.