Engine first start attempt., Couple vacuum leaks, Finally adustable idle. |
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Engine first start attempt., Couple vacuum leaks, Finally adustable idle. |
Olympic 914 |
May 23 2017, 07:30 AM
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#1
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Group: Members Posts: 1,671 Joined: 7-July 11 From: Pittsburgh PA Member No.: 13,287 Region Association: North East States |
Engine first start, Fail.
Yesterday I made the first attempt at starting the engine since rebuild. I had put two gallons of 93 octane gas into the tank and the pump runs as it should when turning the key. I had a timer ready to perform the 20 minute cam break in. I was arrogant enough to believe that the engine would simply start when I finally tried it. WRONG. It caught for a few moments then died. And subsequent attempts gave no better of a response. I had turned the engine over with the coil disconnected to build up oil pressure before attempting the start. And thought I may have run the battery down some. Checking it showed 12.56v resting and 11.44 while cranking. I connected a big boat battery with jumper cables but still no start. It turns over and fires a couple times giving of puffs of exhaust, but does not catch and keep running. Pulled a FI hose and checked that I am getting gas, also pulled two plugs and they are wet with gas. I thought I may have flooded it so I put the battery charger on it and put it back in the garage. This morning I tried it again and the result was the same. It fires a couple times then just cranks. Everything is new. Cap and rotor, points condenser plug wires etc. injectors rebuilt buy Witchhunters , static timed when I put in the distributor. All new vacuum hoses, rebuilt MPS (set to 037 specs) ECU is an unknown but it worked when ran last (in ’89) all the wiring was carefully checked when installed Engine build is as follows. EA 1.7 engine built into a 2056 Using the djet FI with 2.0 parts, intake runners, throttle body, air cleaner, etc. HAM heads ported to RS+ and modified for the 2.0 runners Raby 9590 cam Guess I will start with rechecking the timing and go from there. |
Olympic 914 |
May 31 2017, 09:18 AM
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#2
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Group: Members Posts: 1,671 Joined: 7-July 11 From: Pittsburgh PA Member No.: 13,287 Region Association: North East States |
Went with the JB weld.
It looks like these plenums were put together with the support pieces being separate and added when the top and bottom of the plenum was welded together. looking inside the support piece you can see a ring about 3/16 - 1/4 down on the tops and bottoms (sorry no picture) mine was leaking from that connection. I cleaned it up with a little stone in the dremel and spread some JB weld around in there. I did both support pieces top and bottom, even though only one was leaking. This was the culprit Then got some of those rubber freeze plugs to plug the holes to the intake runners and just used pieces of hose with bolts and such to plug the rest of the vacuum ports. Then another dunk in the laundry tub of water , putting air pressure to it. NO leaks from the plenum, but a few bubbles from around the bolts I had used to plug the hoses. Then the Duct tape I had used to seal the top blew off of where the throttle body mounts. This gave me some confidence in the repair, but thought another test was in order. (since I bought those rubber plugs I may as well use them) Cut a gasket with no hole and bolted the throttle body down to hold it. Then hooked the mity vac pump up and drew 10 in of vacuum. It held vacuum for over 5 minutes, although it did slowly leak down, probably from one of the numerous plugs and connections I had made. I am confident enough in this to say it is repaired. In operation this plenum will never be required to hold a sealed vacuum, and the MPS will adjust for any minuscule amount of air that may leak from the various other connections. It is a lot of extra work but I am happy it isn't something I did wrong when building this engine, OR something that I should have foreseen. Now I just have to wait on the new gaskets to put everything back together. If it was not for this I believe it would have just started and only required a touch of tuning to run good. I bought this plenum off of ebay and can only imagine the headache it must have caused the PO, May even have been the reason another teener owner changed over to carbs. I will update this when everything is back together and thanks to all who made suggestions on things to check. |
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