Rich84
9th December 2014, 12:58 PM
Hi guys,
I had to replace my water outlet a few days ago due to a leak along the seam, which involves removing the intake y-pipe / EGR butterfly housing. Only 1x 10mm bolt holds this on to the engine and then it just pulls out with a bit of maneuvering. I noted the entrance to my intake manifolds were about 25% or more clogged with EGR gunk, which is a tar like mixture of oil and carbon build up. In fact upon removal of the y-pipe, the top most portions of the gunk promptly dislodged themselves and hung off - both about 6x6x30mm worth per intake! Car has 206K, I cleaned the MAP at 170K and noted it is now just as bad as before I cleaned it the first time!
I replaced the coolant flange, which was 5 minutes with the y-pipe removed, then set about cleaning the y-pipe, MAP and entrances to the intake manifolds.
About 1 hour, 1 full can of carb-r-clean, 1 full can of degreaser and a huge collection of absolutely black rags later, I was satisfied that I could not clean the intake manifolds any more without removing them from the vehicle (which was beyond the scope of the tools I had available). The y-pipe and MAP sensor both spotless after having to use numerous scraping instruments to assist with layer after built up layer of hard gritty crud. The MAP I cleaned with contact cleaner, not wanting to hit it with the extra strength carb-r-clean.
So, knowing that a small amount of the carby cleaner would've no doubt made it down into the intake valves, and knowing that this would be fine as I've cleaned all my PETROL vehicles in this manner for the last 15 years, I put it all back together and fired her up - quite a horrendous diesel knock for the first few seconds!! So much I turned it off and double checked nothing was stuck in the visco fan/fan belt! Turned back on. Knocked again but much softer, went away completely after about 30 seconds. The sound was reminiscent of when I once helped a mate start one of his diesel tractors with "Start-ya-bastard" (ether) although that was worse - at the time we really thought "she was gonna throw a leg outta bed!"
In order to test out my results (and test for leaks at the new water outlet) I took it for an extended drive through the Adelaide Hills. Now 5 days and about 750km later the car is running extremely well and I'm looking forward to road tripping it to FNQ next week. Fuel economy is down to 9.0L/100km - just got 930km to a tank which is a record for my normal driving run, so pretty happy with that!
What I'm wondering though is how many people have actually done the next step and cleaned the intake manifold completely and even the entire intake ports on the head? Assuming the remainder of the intake manifold, the intake runners and the intake ports (including the valves :eek:) are just as clogged, would it be worth it to go as far as removing the heads and hot-tanking them at set intervals (168K with the belts?) or just the once for those who have blanked their EGR setup. I know it's a horrendous job, but think about your engine! :angel:
I had to replace my water outlet a few days ago due to a leak along the seam, which involves removing the intake y-pipe / EGR butterfly housing. Only 1x 10mm bolt holds this on to the engine and then it just pulls out with a bit of maneuvering. I noted the entrance to my intake manifolds were about 25% or more clogged with EGR gunk, which is a tar like mixture of oil and carbon build up. In fact upon removal of the y-pipe, the top most portions of the gunk promptly dislodged themselves and hung off - both about 6x6x30mm worth per intake! Car has 206K, I cleaned the MAP at 170K and noted it is now just as bad as before I cleaned it the first time!
I replaced the coolant flange, which was 5 minutes with the y-pipe removed, then set about cleaning the y-pipe, MAP and entrances to the intake manifolds.
About 1 hour, 1 full can of carb-r-clean, 1 full can of degreaser and a huge collection of absolutely black rags later, I was satisfied that I could not clean the intake manifolds any more without removing them from the vehicle (which was beyond the scope of the tools I had available). The y-pipe and MAP sensor both spotless after having to use numerous scraping instruments to assist with layer after built up layer of hard gritty crud. The MAP I cleaned with contact cleaner, not wanting to hit it with the extra strength carb-r-clean.
So, knowing that a small amount of the carby cleaner would've no doubt made it down into the intake valves, and knowing that this would be fine as I've cleaned all my PETROL vehicles in this manner for the last 15 years, I put it all back together and fired her up - quite a horrendous diesel knock for the first few seconds!! So much I turned it off and double checked nothing was stuck in the visco fan/fan belt! Turned back on. Knocked again but much softer, went away completely after about 30 seconds. The sound was reminiscent of when I once helped a mate start one of his diesel tractors with "Start-ya-bastard" (ether) although that was worse - at the time we really thought "she was gonna throw a leg outta bed!"
In order to test out my results (and test for leaks at the new water outlet) I took it for an extended drive through the Adelaide Hills. Now 5 days and about 750km later the car is running extremely well and I'm looking forward to road tripping it to FNQ next week. Fuel economy is down to 9.0L/100km - just got 930km to a tank which is a record for my normal driving run, so pretty happy with that!
What I'm wondering though is how many people have actually done the next step and cleaned the intake manifold completely and even the entire intake ports on the head? Assuming the remainder of the intake manifold, the intake runners and the intake ports (including the valves :eek:) are just as clogged, would it be worth it to go as far as removing the heads and hot-tanking them at set intervals (168K with the belts?) or just the once for those who have blanked their EGR setup. I know it's a horrendous job, but think about your engine! :angel: