7MGE Engine rebuild

[oregonjoe]

Went to install the Alternator and discovered another problem – the lower alternator bracket must go on the block first – before the Air Compressor bracket and fan belt adjuster bracket.



This required taking apart the brackets on the timing cover. The Air compressor bracket wraps around the block and is very difficult to get too with every thing else installed. WORD OF ADVISE _ INSTALL LOWER ALTERNATOR BRACKET FIRST.

[oregonjoe]

I've been researching what type of oil to use for engine break in. Found this web site with some great explanation of what is going on and how to do it correctly

http://www.ntnoa.org/enginebreakin.htm

The bottom line is 30W NON DETERGENT

“The primary deterrent of break in is this heat. Allowing to much heat to build up at the ring to cylinder wall interface will cause the lubricating oil that is present to break down and glaze the cylinder wall surface. This glaze will prevent any further seating of the piston rings.”

"If the wrong type of oil is used initially, or the break-in is too easy, rings and cylinders could (read will) glaze and never seal properly. A fresh cylinder wall needs some medium to high engine loading to get the piston rings to seat properly for good compression but make sure you don't lug or overheat the engine. Use high quality, low viscosity oil (Valvoline 30 weight), no synthetics, too slippery. If synthetics are used during initial break in the rings are sure to glaze over.”

[oregonjoe]

Before I installed the throttle body, I pulled the spark plugs and connected the battery to give the engine a spin to see if I got any oil pressure.

Engine spun but pressure on the gauge. This drew concern since I wanted to be sure I had oil flowing in all the bearings before I started it up.

Checked the panel meter by grounding the lead and it pegged high so I know that was OK.

Then put a OHM meter on the Oil Sender and it read 5.7K which is not what I am used too from oil senders (usually read 30 to 240 Ohms). Kept the Ohm meter on the sender and spun the engine, it read 5.4K, still not right.

Then I read through the TFSM and it did not have any resistance specs for the Oil sender but said it would pulse at different rates to give pressure? HUM?

It did say idle was about 4 PSI and under load about 70 PSI so I would suspect starting would be a lot less then 4 PSI and not move the gauge at all?

Wish I had a mechanical gauge to check against – There is no real way to see if oil is moving around before fire-up?

[oregonjoe]

Well – spinning the engine for the oil test got me excited so I went on a marathon session and moved along in getting the throttle body, exhaust, belts, and radiator back on. The vacuum hose diagram made things pretty simple to connect up. Key thing I found was cleaning the inside of all the hoses with break cleaner made them “tacky” so they stuck better on the fittings. Used RTV on the water hoses expect for the big radiator hoses





Put the fuel pump fuse back in and connected the spark coil. Set the distributor to half way and shut the door.

Key in – turn, it starts.

OIL pressure gauge climbs up to normal pressure. Enough for the night.

[Bill UK]

I read your post 4.38 pm about the oil pressure, so I popped out to start the engine up, looks like you need to fire up the engine to get some revs before any sign of oil pressure as you found out. Excellent work can’t wait to see the video of the total rebuild; you did record it on video didn’t you? I recon you could sell hundreds of copies if not thousands worldwide.

[Krem]

Originally Posted by oregonjoe

Put the fuel pump fuse back in and connected the spark coil. Set the distributor to half way and shut the door.

Key in – turn, it starts.

OIL pressure gauge climbs up to normal pressure. Enough for the night.

Where might I find the fuel pump fuse on the mk3? I'd rather check for this and make sure that's not my problem before I go replacing the fuel filter and/or pump.. also, is this fuse the same thing as the fuel pump relay (which I think is located above the right front wheel well just under the hood?)

Also, what is "normal" oil pressure... this is the first car I've owned where I have a guage for oil pressure and within the two weeks of driving the car, I've noticed it'll go up around 40 psi when I start her up cold... within a few minutes, she's down to 10~12 psi and will build up to 20~25 with engine use/revs... Does this sound normal? too low? Maybe there's something I can check for or do to help keep the pressure up a bit more? Looking at the TSRM, it sounds like i'm running at the minimal threshold for oil pressure, but I also think: "It's nat. aspired... not a turbo, so the pressure shouldn't be towards the high end." but I'm no mechanic... two yrs of HS auto shop (one 9th and other in 12th grade) over a decade ago, I'm not as sharp on the subject as I'd like to be.

[oregonjoe]

Thanks Bill UK for checking that out for me.

The OIL pressure climbs to about mid scale or 40 PSI when cold which is were it has always been for this model. Rev it up and it goes to maybe 50-60, Hard to tell with these gauges. I am going to install a color after market gauge pod from CDI called the vGauge which will give me more accurate temp and pressure readings. Suction mounts to the windshield.

The fuel pump was disabled by pulling the EFI fuse in the fuse pod. Labeled EFI 15 AMP

My solution tot he dipstick problem was JB WELD. Mixed a little of that and now it don't move. Added a little RTV on top for insurance.

[oregonjoe]

Update on initial start – it was not a dream, car actually starts again!.

Ran it for about 15 minutes to get the thermostat open and get some water circulating. No bubbles in the coolant, no leaks on the asphalt.

Did two separate runs of 2 miles each with a cool down in between. Really smooth, just like it was off the show room floor. Has that nice new engine smell.

Got a few extra bolts left to locate. How many extra bolts do you need to still call it successful rebuild?