| ausmini https://www.ausmini.com/forums/ |
|
| burnt inlet valve https://www.ausmini.com/forums/viewtopic.php?f=2&t=93797 |
Page 1 of 1 |
| Author: | i got a mini [ Tue Sep 20, 2016 4:03 pm ] |
| Post subject: | burnt inlet valve |
if i use a full race bigbore 1275cc extractors on a 1100 will it burn the valves out ???as there is not enough back pressure in the exhaust system ???? |
|
| Author: | simon k [ Tue Sep 20, 2016 4:33 pm ] |
| Post subject: | Re: burnt inlet valve |
it'll only burn valves if it's running lean back pressure in any exhaust system is bad no matter what, people confuse back pressure with the need for inertia within the system, and that if you use pipes that are too big then you lose it. Each slug of exhaust creates a vacuum behind it which sucks the exhaust charge from the cylinder. If you use pipes that are too big, then the slug of exhaust doesn't have enough inertia to create the vacuum, so you lose performance. The performance loss is twofold, one is that the exhaust isn't being sucked out, and the other is that the piston has to do more work to push it out So your big bore 'race' extractors on a standard 1100 will probably leave you with bugger all inertia, and you'll go slower |
|
| Author: | i got a mini [ Tue Sep 20, 2016 5:16 pm ] |
| Post subject: | Re: burnt inlet valve |
Thanks Simon so wrong mixture can cause it |
|
| Author: | i got a mini [ Tue Sep 20, 2016 5:23 pm ] |
| Post subject: | Re: burnt inlet valve |
|
|
|
| Author: | deluxe67 [ Tue Sep 20, 2016 7:46 pm ] |
| Post subject: | Re: burnt inlet valve |
How many miles on that cylinder head? |
|
| Author: | i got a mini [ Tue Sep 20, 2016 7:48 pm ] |
| Post subject: | Re: burnt inlet valve |
ummm alot hahah i mean alot bout 160 000 i think |
|
| Author: | carter [ Tue Sep 20, 2016 8:09 pm ] |
| Post subject: | Re: burnt inlet valve |
Actually we have no idea how many kms. I would estimate it would be in excess of 200,000 if not. Lose to 200,000 kms...... They haven't been easy kms though it has been given a hiding...... |
|
| Author: | TK [ Tue Sep 20, 2016 8:11 pm ] |
| Post subject: | Re: burnt inlet valve |
Inlet? |
|
| Author: | i got a mini [ Tue Sep 20, 2016 9:07 pm ] |
| Post subject: | Re: burnt inlet valve |
yep |
|
| Author: | Minicooper4me [ Tue Sep 20, 2016 9:35 pm ] |
| Post subject: | Re: burnt inlet valve |
Valves appear to be pulled into the head, no inserts, spark plug looks shagged, carbon build up, corrosion around water way. You have had a good run out of this head. Appears it needs a full head rebuild. At that mileage, how's the rest of the engine ? |
|
| Author: | drmini in aust [ Tue Sep 20, 2016 9:46 pm ] |
| Post subject: | Re: burnt inlet valve |
And that looks like an exhaust valve. Inlets are the bigger ones and don't burn out. I agree the head needs a full rebuild. |
|
| Author: | i got a mini [ Tue Sep 20, 2016 10:11 pm ] |
| Post subject: | Re: burnt inlet valve |
the motor has had a very hard life very hard when i pulled it out and gave it to my brother carter it was using oil but still went very well still and he has put a lot of ks on it so i think its time for the old girl to be pulled apart and rebuilt again |
|
| Author: | 1071 S [ Wed Sep 21, 2016 11:15 pm ] |
| Post subject: | Re: burnt inlet valve |
i got a mini wrote: yep C#$p... It's an exhaust valve ....or someone's done something extremely weird... Cheers, Ian |
|
| Author: | i got a mini [ Thu Sep 22, 2016 2:02 pm ] |
| Post subject: | Re: burnt inlet valve |
my bad inlet even |
|
| Page 1 of 1 | All times are UTC + 10 hours |
| Powered by phpBB® Forum Software © phpBB Group http://www.phpbb.com/ |
|