Power after head replacement

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Re: Lesharo-owners] Power after head replacement

Unread postby 'Scott.Edwards' » Tue Jun 24, 2014 2:47 pm


I still say, off a tooth on the timing belt. Sorry to say, the symptoms

There are 3 items that could have been off..... distributer, cam, or crank.
Since distributer is attached to cam, that eliminates that variable, leaving
only crank to cam timing.

It's your call, you are there.... but I would re-address this first.

If you are having trouble seeing the timing marks on the cam cog with the
cover on, I have in the past painted the marks white before reassembling the
cover (did lots and lots of vw engines)..... you cannot miss them at that

Cheers, Scott

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Re: Lesharo-owners] Power after head replacement

Unread postby 'derfnarb@yahoo.com [Lesharo-owners] » Tue Jun 24, 2014 3:50 pm

I have rechecked timing. It should be ok. The mechanic has a different set up in his books. The cam and the crankshaft are straight up at #1 tds. Keyhole and mark of crankshaft is straight up and camshaft are straight up w mark on the cover and the square hole on camshaft is up. Just like the picture on page b4-2 Manual timing belt installation . Redid this a few times. I filled with fresh gas. Feeling better as I drive. The local mechanic felt I dont have enough exaust coming out. The last time my pipe got a hole I was told there was nothing left of the cat. After my failure I think maybe some could have knocked loose. The local muffler low budget near me felt I should replace but he was not convinced it would solve power issue when he felt it so I paused on that. No emmissions where I am registered. I am still leaning on this but it could be a fuel pressure issue. Being a little careful on budget. I should probably get the cat replaced. Do you feel
thats the issue? I had this cat plugged prior to replacing it years ago and the simptoms were simular. There are good pics in the book to go by. Also the flange has a small leak. Prior to this repair it had a large leak. Elbow was not honed even though mobility said it was. My point is I wonder if my oxygen sensor is not still adjusting to the change. There is bit of a gassy smell. Sorry this is drawn out. I am still working on this.

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'derfnarb@yahoo.com [Lesharo-owners]

Re: Lesharo-owners] Power after head replacement

Unread postby 'Scott.Edwards' » Tue Jun 24, 2014 4:23 pm

If you loosen the o2 sensor.... not an easy thing! start the engine, rev it
up, listen, remove the o2 sensor.... rev it up.... if it seems to have
power, and lots of back pressure, it very well could be a blacked exhaust

When you have time, the exhaust manifold should be repaired.... welded, or,
grind and glue bond with a manifold rated material..... there are some out
there that have worked for some on this site. That will also fix your smell

I still have some of the gaskets for that o2 extension pipe if you cannot
find them locally.

Do a bit of research, some I think that are in states that don't require
inspections may have bypassed their cat. I don't know enough about the
effects of this, as I am in one of the provinces that check for
emissions..... any way they can squeeze another nickel out of you, they

Take your time..... it'll work out in the end.

Cheers, Scott

--- lesharo-owners 1403647201.M263000P2576Q1
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Re: Lesharo-owners] Power after head replacement

Unread postby 'Scott.Edwards' » Tue Jun 24, 2014 4:34 pm

o2 sensor and computer....

Mine adjusted VERY quickly..... yours should as well.

Does it run fine when cold, then as soon as it wants to move to emission
closed loop it starts to run poorly when trying to accelerate? Mine did....
also check the EGR system, make sure it is operational..... I believe there
is an orifice..... make sure the vacuum relay opens when warm.... I think
yours has a thermal switch on it to control that..... yea, more vacuum lines
to go wrong! It needs vacuum from the manifold (with orifice), and vacuum
from manifold, through switch (open when hot) to activate the diaphragm
allowing the hot exhaust gas to recirculate into the intake manifold.

Check and test your MAP sensor.....

Check the connections where the ignition coil snap into the ignition module.
These sometimes corrode.... reducing spark quality.

Probably enough BLA, BLA, BLA for now.

Cheers, Scott

--- lesharo-owners 1403647201.M450500P2576Q2
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Re: Power after head replacement

Unread postby populuxe59 » Tue Jun 24, 2014 7:52 pm

I can't remember, is there a possibility that gas is OK but that the pick-up for the gas in the tank is getting 98% plugged when the pump turns on?
Fuel filter checked, right? It sure would explain how it can rev freely but then while under load it's not enough and starves the engine.

I don't want to overwhelm you with possibilities but I remember Larry S talking about that a while ago.

I think you got the reply about your Fuel Injectors?? Like other vehicles of that vintage, all 4 squirt at the same time and it wouldn't matter which was which.

Good Luck,
Chris C

--- lesharo-owners 1403658002.M263000P3640Q1
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Re: Lesharo-owners] Power after head replacement

Unread postby Rick Heslop » Tue Jun 24, 2014 7:53 pm

If I remember right, the computers on these relearn each time you start the vehicle. They don't have the ability to remember what happened last time.
Btw I'm leaning to the cat. If you had it changed a few years ago, it should be somewhat easy to remove vs an original one.

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Rick Heslop

Re: Lesharo-owners] Power after head replacement

Unread postby RonOhler » Tue Jun 24, 2014 7:57 pm

Hi Fred,
Remove the oxygen sensor and start it up. If the cat is plugged the open O2 sensor bung will vent enough gases to make a noticeable difference in how it runs. I've had cats so badly damaged back in the day from leaded fuel that the engine would start and then immediately quit. Removing the O2 sensor would allow the vehicle to run. We used to run a length of concrete reinforcing rod through the plugged units to break up the honeycomb. One must be sure of what is being done that you don't leave a loose chunk in the converter that plugs the outlet pipe or muffler. I usually did it with the engine running so that the honeycomb was blown out as it was broken up. This also forced it against the rod so that it would be easier to break up. The units with beads in them had a plug that was removed to empty the beads out.

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Re: Lesharo-owners] Power after head replacement

Unread postby leo wigen » Tue Jun 24, 2014 8:47 pm

Iow fuel pressure will make it lose power, only way to check is put gauge at fuel rail and drive it while watching presure

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leo wigen

Re: Power after head replacement

Unread postby Lee Branch » Wed Jun 25, 2014 12:16 am

Check on the 'net for 'Bosch L-29 Jetronic' information: you will find the connections on the injector wiring are of no consequence. Any wire to any plug will work fine.

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Re: Power after head replacement

Unread postby 'derfnarb@yahoo.com [Lesharo-owners] » Wed Jun 25, 2014 7:46 am

Thanks for the heads up on the oxygen sensor for checking poss plugged cat. The muffler guy wanted to drill a hole. It would have to be welded after. The o2 removal is much better. Lots of good advice over the years here. Hope to make a western rally . I wish it was easy to ship these LS's. I would love to explore many areas and use rhe LS as a camper motel. The long drives getting to many places is out due to the age of these things. I am curious if anyone has had a good experience and reasonable prices sending these maybe by train etc.

--- lesharo-owners 1403701202.M169250P3768Q1
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