hodge Posted November 30, 2009 Share Posted November 30, 2009 hey guys just a quick 1. The battery is going in the boot. am I correct that the earthing strap that goes from the battery to the engine when its in it stock position can just be removed. Quote Link to comment Share on other sites More sharing options...
AlanM Posted November 30, 2009 Share Posted November 30, 2009 I would think you should connect it to the chassis/body Quote Link to comment Share on other sites More sharing options...
hodge Posted November 30, 2009 Author Share Posted November 30, 2009 I woldnt have thought an engine would need earthing though. This earth was the only earth that goes to the battery so I guess its for the batteries benifit not for the engine. Aslong as the battery is earthed correctly in the boot i wouldnt have thought there would be a poblem. Quote Link to comment Share on other sites More sharing options...
stevie_b Posted November 30, 2009 Share Posted November 30, 2009 It's normal for an engine block to be earthed for all cars, although I'm not exactly sure why. Does the spark need the block to be earthed? Each spark plug has one electrical connection (I think) to it. I guess the remainder of the circuit is made up by earthing the block i.e. electrically connecting it to the -ve battery terminal. Quote Link to comment Share on other sites More sharing options...
hodge Posted November 30, 2009 Author Share Posted November 30, 2009 Never looked at it like that matey. Does anyone else have any views on this. Quote Link to comment Share on other sites More sharing options...
heckler Posted November 30, 2009 Share Posted November 30, 2009 pretty much what stevie b said - block needs to be earthed otherwise you'll get no spark! as the "negative" side of the plug is earthed to the battery via the block and chassis. Same goes for almost any of the electrical circuits - all through the chassis. So when you put the bettery in the boot, just connect a strap from the battery to the chassis. Sorted. Quote Link to comment Share on other sites More sharing options...
dude Posted November 30, 2009 Share Posted November 30, 2009 I woldnt have thought an engine would need earthing though. This earth was the only earth that goes to the battery so I guess its for the batteries benifit not for the engine. Aslong as the battery is earthed correctly in the boot i wouldnt have thought there would be a poblem. Sorry dude but this is VERY wrong, you really need to make sure the engine is earthed well or it may try to find its own earths through very inconvinient places like throttle cables and wiring looms etc. I would earth the battery in the boot to the chassis using very good quality cable and proper connections, I have 3 seperate engine earths on mine all with very expensive cable and proper terminals, I know a guy forgot to put his engine earth on an M5 BMW and fried loads of electrics/ecu's etc. Quote Link to comment Share on other sites More sharing options...
hodge Posted November 30, 2009 Author Share Posted November 30, 2009 Now im really pleased I posted this thanks for the help guys. I did earth the engine to the chassis on my last build but was looking to save on cabling and wiring, but if it needs to be there then it needs to be there. Thanks again youve saved me a really big car fire. Quote Link to comment Share on other sites More sharing options...
Ian C Posted November 30, 2009 Share Posted November 30, 2009 Sorry dude but this is VERY wrong, you really need to make sure the engine is earthed well or it may try to find its own earths through very inconvinient places like throttle cables and wiring looms etc. I would earth the battery in the boot to the chassis using very good quality cable and proper connections, I have 3 seperate engine earths on mine all with very expensive cable and proper terminals, I know a guy forgot to put his engine earth on an M5 BMW and fried loads of electrics/ecu's etc. Agreed. I had a ghastly electrical problem once and it was caused by the earth strap near the dipstick coming off the engine. All other earths were intact and fine and yet this one missing caused the car to fail to start and all sorts of odd light and gauge behaviour! -Ian Quote Link to comment Share on other sites More sharing options...
Andy Blyth Posted November 30, 2009 Share Posted November 30, 2009 You definately need a good earth bonding between the engine and the chassis if you are moving the battery to the boot. It's for the return current of the starter motor. Without the bonding, the engine is as good as isolated from the chassis through rubber mountings etc. Quote Link to comment Share on other sites More sharing options...
michel lane Posted November 30, 2009 Share Posted November 30, 2009 make sure you earth the wiring loom between the lower runner of the intake . There are 2 earthing points there required. This connects to the ecu . Hand some cars with conversions without these and the ecu went all funny after awhile. replacement units had to be fitted. As Dude states, you do need it. I have 3 earthing points on my car. Quote Link to comment Share on other sites More sharing options...
garethr Posted November 30, 2009 Share Posted November 30, 2009 So what's the best way to make the earth? Through the body, or by running a hefty cable from the boot to the engine bay? Quote Link to comment Share on other sites More sharing options...
Andy Blyth Posted November 30, 2009 Share Posted November 30, 2009 So what's the best way to make the earth? Through the body, or by running a hefty cable from the boot to the engine bay? Through the body is fine Quote Link to comment Share on other sites More sharing options...
barneybrendan Posted January 23, 2011 Share Posted January 23, 2011 what size cable do you run from the boot. Quote Link to comment Share on other sites More sharing options...
Suprab1 Posted January 24, 2011 Share Posted January 24, 2011 So what's the best way to make the earth? Through the body, or by running a hefty cable from the boot to the engine bay? Always better to keep an earth as short as possible. Quote Link to comment Share on other sites More sharing options...
Guest blueangel Posted January 24, 2011 Share Posted January 24, 2011 when o relocated the battery i earthed the battery in the boot to the body and the original earth in the engine bay i also connected to the body is this ok all seems to be running fine Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.