Power Loss 1st to 2nd Na6

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MosieurCinq
Driver
Posts: 48
Joined: Thu Aug 01, 2013 8:01 pm
Vehicle: NA6

Power Loss 1st to 2nd Na6

Postby MosieurCinq » Fri Jun 19, 2015 5:20 pm

Hi all

Recently had the engine changed on my Na6 (Long story, will cover later)

The previous engine had the timing advanced and drove great, this new engine is much lower in Kms but is a factory 1.6 and hasnt had anything done.

When shifting between 1st and 2nd the engine bogs, absolutely loses revs/power until the revs slowly climb and we continue on our way.
This doesnt happen in other gears, or only at a specific rev point.

Is it just that its doing it more than I am used to and this is normal? Or should I be having a hunt around to see what the Mech's may have missed?

Any input would be great, or if you have similar issues/resolutions!

Regards

speed
Speed Racer
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Joined: Sun Jan 19, 2014 9:52 am
Vehicle: NA6
Location: Lugarno, Sydney

Re: Power Loss 1st to 2nd Na6

Postby speed » Fri Jun 19, 2015 5:43 pm

Was the replacement engine bog free when first installed?

I guess it depends how much bog we are talking about. If it's really sluggish then something is as miss.

You could try and advance the timing to up to 14 degrees and see the difference.

Otherwise I'd be checking and replacing air filter, plugs, leads, coolant and O2 sensor, fuel pump, CAS and check your coils are good.

Another thing to look for would be the dreaded SNC failure. Check to see if the crank pulley is wobbling and if so the key way is stuffed. Can also happen on long nose engines so definitely worth checking.

Personally I'd start with the free stuff then move on to plugs and leads and check the coils. If your timing oscillates or the engine cuts with heat, replace the cas.

Hope that helps give you a good starting point.

Best of luck and let us no how you get on :)
NA6 turbo - 140kw atw - not the most powerful but so much fun :D

project.r.racing
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Location: Glasshouse Mountains, QLD

Re: Power Loss 1st to 2nd Na6

Postby project.r.racing » Fri Jun 19, 2015 5:44 pm

clutch not installed correctly.

speed
Speed Racer
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Joined: Sun Jan 19, 2014 9:52 am
Vehicle: NA6
Location: Lugarno, Sydney

Re: Power Loss 1st to 2nd Na6

Postby speed » Fri Jun 19, 2015 5:45 pm

I should have also suggested a compression test but it all depends on the state of this new engine.
NA6 turbo - 140kw atw - not the most powerful but so much fun :D

MosieurCinq
Driver
Posts: 48
Joined: Thu Aug 01, 2013 8:01 pm
Vehicle: NA6

Re: Power Loss 1st to 2nd Na6

Postby MosieurCinq » Fri Jun 19, 2015 5:51 pm

I can't confirm that it was bog free when it was installed as the mechanic's shop organised the whole thing while I was away, everything except coils are new or like-new so ill be double checking over things that weren't replaced.

Thankfully the mechanic did his research and understands the SNC issue and has replaced the bolt, as well as lining it up to monitor if it is moving over the next few weeks.
Thanks Speed, Ill do the basics first but it just seemed odd that it was only 1st to second and 3rd to 2nd at low rpms.

With all the gaskets and seals changed I would have hoped for a compression test but I think it would be worth me double checking it.

Project R, would there be a way of confirming this? it seems like it could be a likely problem (possibly) but not sure on the best way forward with checking it.

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KevGoat
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Re: Power Loss 1st to 2nd Na6

Postby KevGoat » Fri Jun 19, 2015 7:18 pm

This car had a loose clutch fork when I had it. Didn't affect anything, but use to rattle on down shifts is how I found out. Just wondering if those with more knowledge would know if this could affect it? Maybe it's moved or not working properly since the engine been removed/replaced?

eskimo
Driver
Posts: 31
Joined: Sat Jul 24, 2010 9:37 am
Vehicle: Clubman

Re: Power Loss 1st to 2nd Na6

Postby eskimo » Tue Jun 23, 2015 8:57 pm

Was the timing belt replaced?, sounds like one or possibly both cams are possibly one tooth out.
Does the engine rev out and the car not accelerate or does it neither rev nor accelerate? if the later it's not a clutch issue.

Mr Morlock
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Location: Melbourne

Re: Power Loss 1st to 2nd Na6

Postby Mr Morlock » Tue Jun 23, 2015 11:35 pm

take it back to the mechanic and get them to drive the vehicle and do some fault diagnosis. Of course it should accelerate cleanly through the gears.


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