Friday, October 8, 2010

Timing Belt

Next project up is to change the timing belt on the Subaru engine. I purchased a Gates complete kit with new tensioner and pulleys/gears from the local CarQuest since I just know very little about this engine and access the timing belt is a lot easier on the stand then in the car.
First step is to remove the crank pulley and tensioner. Then on to the plastic timing belt cover. Easy enough
For the most part, this was a pretty straight forward project. I followed a technical forum write up by Meaty on North American Subaru Impreza Owners Club Website as well as the instructions that came with the kit and the pdf service manual, which I downloaded from Ken Gilbert's Website. All three were slightly different in instruction, so I had to make some decisions along the way.

The biggest worry I had was regarding the right side cam gear timing mark. I actually had two different marks, a white paint dot and an engraved dash in the gear face itself with pink paint.
In the end, I went with the physical indented dash with the pink dot. I followed the instructions, lined the belt up appropriately, double checked everything, and then pulled the tensioner key to put the belt under tension.
The time of judgement came after when I rotated the crank two full revolutions to see if all three timing markets still lined up again.
Yes = Did it right
No = Did it wrong
My results YES = Did it right!

Air Intake Manifold and Throttle Body

Here is a top look at the air intake manifold and throttle body (taped up). As it sits in stock position, the manifold has the throttle body facing toward the transmission. Fine in a Subaru, but in a Bus it won't work.

If you notice how close the throttle body extends in relation to the engine mating surface for the transmission, and if you think about the alignment of the VW transmission bellhouse almost inline with the firewall above, you can see that there is going to be a conflict. There is no way to attach an air intake pipe/filter to the throttle body without interfering with the firewall and gas tank.

The most common remedy for this is to flip the throttle body 180* and then flip the wiring harness 180* again so the fuel injectors still fire in the correct order. The problem with this solution is that the throttle body then intrudes into the space that the alternator normally sits, requiring a custom fabricated bracket system to reposition the alternator where the a/c compressor normally sits.

My dilemma is that I am not sure I want to screw around with fabricating a bracket, and there are none to purchase aftermarket right now. Richard at RJES is potentially going to sell an off the shelf alternator bracket to help this problem, but it is not available currently. An added problem is that this solution eliminates the possibility of an A/C compressor since the alternator has to be be repositioned to the spot the A/C compressor us ally sits. I kind of like the idea of retaining the A/C compressor so we can have air conditioning. Windows down with a two year old and a 10 month old is not always a good thing.

However, the alternative to reversing the manifold is to modify the firewall or potentially run without the firewall (may not be a smart choice without a fire repression system installed). AND, I don't know of the air intake pipe will even fit without the firewall due to the gas tank. I have to mock the engine up in place to see what type of, if any at all, clearance I have.

In the meantime, I pulled the intake manifold off.

The coolant heater manifold sit underneath the intake manifold.

A lot of people doing this conversion on Vanagon VW have the coolant manifold reversed to better fit and locate with the original Vanagaon coolant lines, which sit on the top passenger side of the engine compartment. Since I don't have stock radiator or lines to mate up, I don't have to reverse the coolant manifold. However, I am considering doing so since most/all radiator coolant schematics are based on this manifold being reversed. It is an added cost but it would make routing and plumbing against common schematics very easy. Tom Shiels has quite a bit of excellent info on coolant and radiator set ups on his Website although it is all for Vanagon conversions not Bays like mine.
The decision to reverse the manifold or modify the firewall/fuel tank will have to wait until I can roll the engine under the bus and jack it up into rough position. Before I do that, I have to finish the tank restore project and replace the timing belt on the Subaru motor.

Fuel Tank Restore

While I had the engine out, I decided to pull the gas tank. I had noticed that the filler tube on the gas inlet was cracked and potentially the cause for some of the strong gas fume smell inside the bus (we had to roll windows down quite a bit on the drive back from Santa Fe). The only way to replace this piece is to remove it from the inside, which requires pulling the tank out , which requires removing the engine.

Pulling the tank wasn't too hard with the engine out. I followed Richard Atwell's DIY Fuel Tank Restore thread. I was shocked at the amount of rats nest hiding out behind the firewall after pulling it off.

As I looked closer, and while holding my nose, I saw the skull of the culprit!

It turns out it wasn't only the skull; it was the entire skeletal system from skull to tail and toes included! Oh man, did it smell. Pee and poop coated the bottom of the tank bay and I am still spraying it down and scrubbing it out. I can't get the piss smell out of my nose...

The tank itself looked pretty good, dirty, but no noticeable holes.

I wonder what rat hair and pee/shit does in regard to resistance drop? My gas gauge never did work below the half way mark...maybe I know why now (pic of the sending unit).

I ordered a POR-15 Fuel Tank repair kit from Don at the POR-15 outlet on eBay:

POR-15 AUTO FUEL TANK REPAIR KIT GENUINE POR15 (Item Number: 230383638934)

I opted to go the full kit rather then follow Atwell's mueratic acid route.

I am planning to prep the tank and apply the POR-15 this weekend.

I also ordered a new fuel filler neck (PN211 201 119) and a sending unit (PN211 919 051A) from Bus Depot and am awaiting their arrival. Finally, I have ordered 7.5 mm fuel line hose and clamps from Smallcar and will replace all fuel hose from tank to engine for safety's sake.

I hope to have the tank done and reinstalled by the end of the weekend. Once I have it reinstalled, I need to carefully consider the throttle body position on the Subaru air intake manifold. In its current position, it interferes with the firewall and possibly the tank. The solution to this is to flip the manifold around, rotate the wiring 180* and create a custom alternator mount since the stock location won't fit with the throttle body flipped around.

I honestly am considering keeping the air intake and throttle body stock so I can retain the alternator and a/c compressor in stock location as well. However, this will mean either not installing the firewall or modifying the firewall to accept the air intake fittings. I don't even know if it is possible until I roll the engine under and mock it up into rough position to eyeball everything.

Friday, October 1, 2010

Airconditioning cooler unit

While crawling around and under the bus after first buying it, I realized that there was an airconditioning cooler mounted between teh frame rails. It has a vented cover plate to direct airflow through the cooler and looked to be original.

I poked around and peared above the system to see what I can discover, and low and behold two fans strattled the hot air pipe the runs the center of the bus toward the front.

I started to get excited about the possibility of reusing parts and bits from this set up for a radiator set up between the rails. I decided to pull the unit down and explore in more detail. This is the shot I took after I removed it from the bus, with the vented plate has been removed and you can see the aironditioning cooler.

Here is a closer shot of the two vent rows that supposedly direct air up and through the cooler. I haven't measured the stock Subaru raditator yet, but I believe I should be shooting for 1.5 or even two times the capacity over stock for my application. I am not sure if the dimensions of this vented plate will fit the size of radiator I will need! If anyone is running a certain sized radiator in a vanagon conversion with a Subie engine, please let me know the radiator dimensions.

Here are the original stock fans on the top of the unit that force air down through the cooler at slower speeds I suppose (not sure how they were intended to function on an airconditioner).

Next step is to determine the right sized radiator and then decide if I can buy stock from a different vehicle or if I will need to have one custom made. Once I know the size, I can determine whether the vented cover plate is going to fit.