2.0 LNF Engine: How To: Valve Gunk/Coking Removal
#151
Yelcal valve gunk has less of a chance to kill you than a lightning strike would. You should be more worried about other drivers on the road=the biggest risk.
You can still put on high mileage without having to do any gunk removal maintenance. There was a dude on here 250,000+km and he never even sea foamed it.
You can still put on high mileage without having to do any gunk removal maintenance. There was a dude on here 250,000+km and he never even sea foamed it.
#152
UPDATE:
The car is now at 34.2 thousand miles. I decided to do a check up on the valves. The inlet of the turbo looks brand new and sparkling, so the oil separator must be doing the job. However, I believe my PCV valve in the intake manifold has failed. There is a river of oil at the bottom of the intake manifold and my valves are quickly on their way to being terrible again.
Compared with the end result of my cleaning less than 7 months ago, I am shocked to see how much build up there is.
The car is now at 34.2 thousand miles. I decided to do a check up on the valves. The inlet of the turbo looks brand new and sparkling, so the oil separator must be doing the job. However, I believe my PCV valve in the intake manifold has failed. There is a river of oil at the bottom of the intake manifold and my valves are quickly on their way to being terrible again.
Compared with the end result of my cleaning less than 7 months ago, I am shocked to see how much build up there is.
"No one thing will fix this issue entirely: driving cycles, fuel quality and octane, low ash engine oil are all important additional factors to consider.
The driving cycle.
The driving cycle I refer to, is to avoid low rev high boost situations , extended low rev cruising and short 1-3 mile start /stop / park driving. Add long idling time in winter as well; these driving cycles may contribute to low inlet valve temperature.(So) There is no one single solution, although we have found good gains with the PCV upgrade so far. There are other important things to consider. The suggested changes for your car include:
• using low ash engine oil
• change in your driving routine, avoiding low rev/high boost driving.
• always use tier one gasoline
• always use 93 octane or better"
I dont recall the member who got 250,000 km out of his car without coking, but I would be surprised, although clearly I beleive that the driving cycle influences this stuff a great deal. And other cars are worse; Audi, BMW. VW. Toyota etc all have these issues. The GM 3.6 V.6 DI has issues as well and one GM TSB includes blocking a rocker cover vent port. Bear in mind that V6 have two covers before you rush out to block your vent thinking this could help (lol)
#154
Yeah I usually stay 4th unless doing 90+kph. And my car's seen many extended periods of 125kph-130kph=2800rpm-3000rpm long haul drives. Unfortunately hasn't seen 94 octane, I just stick to the 91 unless my hometown gets some 94. But it is always Petro-Canada or Esso gas. Love those reward programs.
#155
Even though I haven't had the chance to check my valves yet, I want to add this to my spring maintenance plan. I'm new to the LNF scene, but I really want to get my valves cleaned before I order Powell's oil seperator. Is this really hard to do by yourself or should I let someone experienced take care of it?
#156
Removing the IM isn't terribly complicated. It requires some weird contorting in order to pull it out. If you take your time, and keep track of where the vacuum hoses and wires go, not a big deal. I never did the walnut blasting, so I don't know if that is very complicated. I would say that if you're comfortable with making sure the valves are in the right position and torquing the nuts properly then you'll be alright. If the only thing you've done is an oil change then you may want some help while you do it.
#157
It's just time consuming. Be cautious. Tape everything up properly before blasting.
Taking your time is the best advice I can give. The instructions on here are pretty good. I would consider myself a very average mechanic.
Taking your time is the best advice I can give. The instructions on here are pretty good. I would consider myself a very average mechanic.
#158
I'm coming from an L61 on a Pontiac Sunfire. I changed my own oil, have done spark plugs, changed accessory belt and changed my front struts and brakes. I can say I have some mechanical know-how, but the turbocharged LNF seems a whole new beast to me. What do you guys think?
#160
1st day, take your time with taking off the intake manifold
2nd day, clean valves and put it back together.
Once you have taken the intake manifold off you will be able to put it back together twice as fast.
Oh and make sure to get a new intake manifold gasket for good measure.
#163
#165
Little to nothing if it looks like OPs valves. Maybe if you just walnut blasted them it might help, but I'm sure you'd get better results from CRC's GDI intake valve cleaner every oil change or every other oil change.
#166
#167
^^^ this. I am currently working on modifiying the inlet manifold to eliminate that pathway for blow by gasses to the inlet valves.
More news as it happens. One car has been done that way and its working well. PS I have also seen some phenolic spacers made wrong so the stock pcv can dislodge , and travel so the O ring is no longer sealing at the head/inlet manifold face, and allows lots of boost into the crank case. Not good.
More news as it happens. One car has been done that way and its working well. PS I have also seen some phenolic spacers made wrong so the stock pcv can dislodge , and travel so the O ring is no longer sealing at the head/inlet manifold face, and allows lots of boost into the crank case. Not good.
#168
Hello all,
So Im in the process of doing this. Intake manifold is off and my gunk is just as bad as OP's! But one question, the guy at NAPA is telling me that we don't have an intake manifold gasket but just an O-ring set to replace the gasket that's in place. This doesn't sound right. Is it true?
So Im in the process of doing this. Intake manifold is off and my gunk is just as bad as OP's! But one question, the guy at NAPA is telling me that we don't have an intake manifold gasket but just an O-ring set to replace the gasket that's in place. This doesn't sound right. Is it true?
#169
Hello all,
So Im in the process of doing this. Intake manifold is off and my gunk is just as bad as OP's! But one question, the guy at NAPA is telling me that we don't have an intake manifold gasket but just an O-ring set to replace the gasket that's in place. This doesn't sound right. Is it true?
So Im in the process of doing this. Intake manifold is off and my gunk is just as bad as OP's! But one question, the guy at NAPA is telling me that we don't have an intake manifold gasket but just an O-ring set to replace the gasket that's in place. This doesn't sound right. Is it true?
Order from crate engine depot.
#170
x2. That guy doesnt understand the difference between a turbocharged 2.0LNF engine and a 2.2/2.4 L61/LE5 engine (which is the cobalt that has rubber o-rings for the intake mani gasket)
#172
This is what I do^^^ and my car is at 94k never had the vavles done 0 issues with anything only a maf sensors and bpv.
#173