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Engine building scares me
Irony - 13/9/10 at 11:07 PM

I am building my RV8 at the moment and I am finding the task quite stressful. I had a head bolt snap on me which I removed thankfully with ease. But now with every bolt I torque up (with a brand spanking new torque wrench) I am nervous as hell. When you need to go that extra 1/4 turn to make the wrench click I start thinking of snapped bolts, ruined threads, helicoil kits and pound notes being placed in a fire.

Thankfully I am getting there and I think I am about half way. All the internals are done and the manifold is next, then the engine mounts the the flywheel, clutch and gearbox. Then its going in the car.

MikeRJ - 13/9/10 at 11:14 PM

You think building it is stressful, wait until you start it for the first time! You will be in full paranoia mode worrying about every little sound

Canada EH! - 14/9/10 at 01:02 AM

Being as you are building an ali engine the threads usually strip first, suggest a little light oil or anti seize compound on the threads before inserting the bolts. Most times this is not recommended but with ali it is sometimes necessary.

omega0684 - 14/9/10 at 06:34 AM

dont know about the V8's myself (yet) but on a pinto you are given sachets of oil to put on the threads of the head bolts when you replace them.

madteg - 14/9/10 at 06:58 AM

I think its the rover V8 that you can have trouble priminig the oil pump, he he he

mark chandler - 14/9/10 at 07:12 AM

You have probally been supplied with stretch bolts, the manual will say torque to a set poundage, with stretch bolts you do to a lesser degree then tighten up by 180 degree's.

Assuming this the bolts will feel easier to turn as you hit the elastic point and will never reach the full torque but snap.

They feel horrible but all later RV8's use them....

mcerd1 - 14/9/10 at 07:38 AM

a little bit of fear is probably a good thing - it'll keep you on your toes and you'll probably check everything 3 times

quote:
Originally posted by omega0684
dont know about the V8's myself (yet) but on a pinto you are given sachets of oil to put on the threads of the head bolts when you replace them.
where did you get them from ? (I've not got any for mine )

[Edited on 14/9/2010 by mcerd1]

fesycresy - 14/9/10 at 07:53 AM

100% correct.

Here's a good read:

RPi Link


quote:
Originally posted by madteg
I think its the rover V8 that you can have trouble priminig the oil pump, he he he

02GF74 - 14/9/10 at 08:23 AM

hmmm ... torquing up engine bolts has never worried me.

with the Rover, run a tap down the bolt holes or a bolt with good thred with a cut to clean up the threads.

I've re-used head bolts - clean them up ideally with a die or wire brush.

drop of paraffin for lubrication on the threads and do them up in stages.

omit the fifth bolt from each cylinder in the heads - or do up to pitiful torque, less than 20 lbft (again see RPi for more info if you don't know wot I'm on about.)

The head and rocker bolts are so oversized they should not snap unless some numpty has over done them beforehand, it is the little piddly bolts to hod the timing cover and water pump that should be a concern - ideally replace those than re-use (no prizes for who had one snap on their engine, and of course it is always the last one you do up requireing the whole caboodle to be removed - IIRC those bolts are 1/4 UNF).

Irony - 14/9/10 at 08:42 AM

Thanks for the replies. I don't think I am doing anything wrong and I am reading the official Land Rover rebuilding guide and the haynes manual as I go along.

Its more my jangling nerves that are the problem! I should probably just 'man up' as they say at work.

adithorp - 14/9/10 at 10:09 AM

Bolts and studs break. Sometimes it's because they're faulty, or someone else has previously damaged them and sometimes it'll be your fault. Thats just the way it is. Experience will reduce the number you break as you start to know the feel of one starting to go... only takes about 10 years of doing it every day. Breaking things is just part of learning although for most mechanics this is reinforced by someone screaming at them... questioning thier parentage is usually invoved.

Oil the treads and under the head of the bolt, clean and blow out the holes (you don't want a hydralic lock caused by oil down the hole), tighten to below the required torque and then final torque the bolts in one movement.

adrian

r1_pete - 14/9/10 at 10:12 AM

quote:
Originally posted by madteg
I think its the rover V8 that you can have trouble priminig the oil pump, he he he


It is, you need to pack the pump with vaselene, which creates a better vacuum to draw the oil up the feed pipe. Once running the vas dissipates into the oil and the oil seals the pump gears.....

[Edited on 14/9/10 by r1_pete]

mad4x4 - 14/9/10 at 10:45 AM

quote:
Originally posted by madteg
I think its the rover V8 that you can have trouble priminig the oil pump, he he he


I did and knackered an engine = so the next one I made up a tool that drove it off a cordless drill from the Dizzy Drive..... This trick is all over the Landy forums

[Edited on 14/909/10 by mad4x4]

PuppiesBalls - 14/9/10 at 12:05 PM

quote:
Originally posted by Canada EH!
Being as you are building an ali engine the threads usually strip first, suggest a little light oil or anti seize compound on the threads before inserting the bolts. Most times this is not recommended but with ali it is sometimes necessary.

Putting oil on the threads means you that because theres less friction/torque required to turn the bolt, that when tightening to the same figure you are pulling harder against the threads & tightening up to a greater force.

My standard head bolts should be tightened to 71ft.lbs but when using ARP assembly lube you only need to tighten to 52ft.lbs because less of the force your putting in to turning the bolt is used to overcome the friction of the thread

Irony - 14/9/10 at 12:18 PM

I'll make the tool up for priming the engine when the big 'switch on' in required. You can even buy them from t'bay these days.

jollygreengiant - 14/9/10 at 06:19 PM

quote:
Originally posted by madteg
I think its the rover V8 that you can have trouble priminig the oil pump, he he he


Never had a problem with one. Just pack the oil pump internals with vaseline. Then make sure that the last thing you fit before starting is the distributor (this drives the oil pump, so you can turn the engine without unpacking the oil pump) and then away you go. The worst I ever suffered was one of the lifters sounded like it was eating a mouse for about 500 miles.

If you want stress, build up a Ford 2.0 litre, 8 valve, twin cam for the first time and then start that. I guarantee that your first instinct will be to turn it off and then wonder WHAT you left loose in the engine. They sound like you have left everything lose, and the cure is to put you foot on the throttle and take the revs up to between 2,000 and 4,000 rpm. It goes against all instinct.

rusty nuts - 14/9/10 at 07:13 PM

Just wait until the engine starts to warm up and the smoke appears

scudderfish - 14/9/10 at 07:39 PM

quote:
Originally posted by rusty nuts
Just wait until the engine starts to warm up and the smoke appears


That'll be the small leak from the rocker covers dripping onto the exhaust manifolds