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Engine Specific Info and Questions => IDI Engine => Topic started by: oblique on January 26, 2025, 03:06:53 pm
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So finally swapped out the original 1.5d. Hot compression numbers were: 510, 450, 460, 425 and the air filter was soaked with oil after 4000km.
Swapped in a ME 1.6NA which I had bored .5mm over with Taiwan pistons, replaced rings with Goetze, crank checked and polished by reputable shop, all new KS bearings, NOS factory reman rods. Cylinder head was oe Nos with used valvetrain, rebuilt by machine shop. Measured protrusion and used Nos OE 1 hole gasket.
I've got 500km on the swap and Ive got oil dripping out of exhaust seams. It will start in the cold (-12C, 10F) but idle badly, have little power, sometimes even shut down, until it warms up. Power seems good when warm but I swapped in a 5spd 4S to replace the old 4spd so its really hard to compare.
I assumed that because the block is bored (ie. the bores are perfectly round) that breakin is minimal? Or did I F*** something up.
thank you.
(https://i.ibb.co/3zTsQPP/20250124-173138.jpg) (https://ibb.co/TLwTdNN)
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Breaking in miles/kms depends on how it is driven. To really break one in you need to cycle the RPMs up and down. Use the engine for braking before hitting the brakes—higher RPMs in a lower gear, that sort of thing.
If you just get in and take it on a long road trip at a steady RPM the rings don't really get to wear into the cylinder.
Could the oil be a result of a build-up in the exhaust from when the old engine was pouring it into the engine? How hot do you run it? Or should I really say how long do you have for a drive each day? It might take a bit of time to get it all out of the muffler and pipes. I know when my turbo lost a seal on the exhaust side I had oil pouring out for a while, mostly because my trips are not long in town.
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Those compression numbers were on the old 1.5 engine right?
Got compression numbers for the new engine?
Oil in the exhaust?
If it was burning in the engine, it wouldn't come out as oil.
It would maybe stick a little like burning oil when running.
And I'm not sure the valves could leak that much.
Are you using the cold start lever when starting it cold?
How does it act when you push it in when cold, just after starting?
Your cold start lever can tell you a lot about how well your timing is set,
especially during very cold weather.
Kinda sounds like it should be advanced a bit.
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In terms of breaking: Ive been driving it to work mostly but had a bad leak in the old used flexpipe I put on it so been keeping my foot off the gas. Guess I should get on it a bit more. The exhaust is all different: dual exhaust manifold and downpipe from a gasser, no oil contam.
No part of the.old motor was used for this build.
Yes, those are comp numbers for the old one. In terms of starting, advance fully pulled out. If I dont have it out on a cold motning it will barely idle if at all. Its a fresh Giles perf pump, double checked timing at 0.95
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If I had this situation I would loosen the nuts and bolt that hold the IP and push it toward the engine a wee bit and see if that helps. Sometimes you can have the IP measured out to a gnats eyebrow and when doing the take up on the slack you lose some of that measurement. Bump the pump for me.
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Yep, .95 sounds like it's a little low.
Often, when the cold start lever is set right.
It will slow down the engine when it's pulled.
Have to push it in to get the RPMs up and when it starts to fire pull the knob.
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Just to be clear here - Giles specifies 0.95 as default position for his performance stuff. I will try to push it a little though, say by .03?
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i'd try advancing the timing a little, did you use new injectors?
the old engine looked pretty healthy, could it have been a plugged up valve cover filter? did you use the old valve cover on the new engine?
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Injectors are rebuilt by me using good used, cleaned nozzles. They are mixed 273 and 293 but I don think that matters.
After sitting for 31 years I think the old motor had some corrosion issues on #4...nothing from the old 1.5 was used on the 1.6.
I will try moving the pump a bit.
Hows the pump, Steve?
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Even though Giles suggests .95.
It's pretty common to go to 1.05 on stock TD setups.
What breaking pressure did giles tell you to use with his pump?
I'm jealous by the way. Always wanted a Giles pump.
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Giles builds a lot of advance into his pumps so 0.95 is the reference with his stuff.
Checked timing today...it was .90...moved the pump in a bit and its much better.
In terms of injectors, they stay at factory pressures regardless of pump config.
Fixed the exhaust as well and I've been pushing it a bit...Im not sure the Rabbit is any slower than my mk2 1.6TD...it really moves. Hard to believe its an NA motor.
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Turbo pumps like a bit of advance. That is what I have found, and I also noticed they don't need the cold start cable pulled very often.
So you bumped the Pump and it ran better. I thought it would.
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Well, my issues continue. The oil has stopped...that was likely a combination of blowby during breakin and a valve taking time to seat...the head is new but valvetrain had miles.
Now I have a loping, 'missing' idle and throttle hesitation.
When I retimed the pump it was at .92 or so...set it back up to right around .97. It seemed to help but the weather was warmer at the time...we are back to 10F in the mornings.
Even with the engine warm I get low-to-mid throttle hesitation and rough idle.
Even if my machinist bored the cylinders too big (he mostly does old big block domestics) would that explain it? Is it time for a compression test...I've got maybe 2500miles on it, but maybe the last thousand or so has been harder driving.
Or is it the pump.
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Doing a compression test won't hurt and might even help figure this out. Run the numbers and then look at the pump for issues. You might just be able to increase the RPM 100 and be back to good.
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Do you have clear fuel lines?
The picture above shows the rubber ones.
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ok so warm comp test was 460-460-470-480
BUT...in the process I noticed a leaky injector....taking it out revealed fuel in the bore as well...turns out the nozzle wasnt seated flat as there was corrosion on the inside of the injector body that the nozzle sits in.
Idles better for sure, we will see how it starts up cold.
The return line is rubber but the supply is the translucent blue one that McMaster-Carr sells. no bubbles in there.
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I took an old heat shield, cut an emory cloth disc over it,
and a small, long bolt through it.
It's used to clean up the area where the heat shield sits.
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the issue was the injector itself...the nozzle wasnt seated parallel to the body...there was built up corrosion in the bottom half of the injector body that was preventing it from sitting straight in the injector body...so wasnt sealing against heatshield OR injector internals.
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See doing a comp test on it solved all your worldly problems. Just like I thought. Ahem, ahem.
Nice to find those never knew that before things on the car as you wrench on it. Definitely a great find. Hope all is well now. MPG should go up as well as smoothed out idle speed.
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The saga continues...
Turns out I was running full synthetic the whole time....Mopar Diesel DPF 10902 is full despite no mention on the labels. Switched to T4, now my exhaust smells like cats a$$hole.
I get hesitation at low throttle position. Coasting in town the car will start to bog down and lurch forward and back, I have to give it juice to get over it but then my 1.6 powerplant takes over and puts me back in my seat..since my floor and seat support bridge is gone I go WAY back.
Cold start issues persist.
Going to give it some more miles with the other oil but it doesnt explain everything, I dont think.
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I'd try advancing it more than .97
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that lurching sounds like fuel pump issues;
- air in the fuel lines
- give it some more fuel (fuel screw), 1/4 turn
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What typically causes white smoke on a warm motor without the advance pulled? I get a fair amount even on medium accel. Am I still dealing with timing or do I have injector issues...I rebuilt and set them up properly but with used nozzles that I cleaned and polished.
Haven't adjusted anything yet.
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White smoke is either bad timing, or a leak in the cooling system as far as I know. Bump that timing up to 1.0 - 1.05 and see if it goes away.