leakdown test bad, what should I do?
#1
Junior Member
Thread Starter
iTrader: (4)
Join Date: Oct 2007
Location: santa cruz
Posts: 245
Total Cats: 1
leakdown test bad, what should I do?
This is my first post. Been lurking for months.
I bought a clean ‘94 with 90k miles a few months ago. I had my credit card out and ready to order the BEGi S kit but I decided to first do the basic diagnostics…
Compression test was: 175, 165, 165, 170
Seemed good enough.
Vacuum was 18 in at idle.
Timing is 14* and I run 91 California crap gas. Runs good.
Then I did a leakdown test. The leakage was equally terrible in all four cylinders. The leakage past the rings was so bad, I could actually hear the oil gargling through the dipstick tube (with the oil filler cap in place).
I burn 1qt of 20w-50 dino per 300 miles and the oil turns jet-black within 50 miles. I’ve tried 6 or 7 different oils and weights with similar results.
I don’t think this motor qualifies for a turbo.
Power goal: If I had to state a power goal, I’d say 250whp. Doing it in steps would be fine.
Budget: If I had to state a budget, I’d say $7k.
If you’ve made it through this long post, thank you. My reason for posting is to get advice. I’m not quite sure what to do.
My original plan was to:
1) get bigger injectors, MSPNP and wideband installed. Sort out the timing and fuel.
2) then install the BEGi S kit.
3) then upgrade gradually.
But it looks like I need to rebuild/replace my motor first.
With my budget and hp goals, should I:
1) build a stout shortblock (forged pistons/rods) and port the head and extrude hone the intake? After machining and parts, that would be at least $3k, correct? Leaving me with $4k for other FI parts…
2) Or should I find a low mileage long block, leaving me with more cash for better FI parts?
3) Leave it as-is and boost it with crappy rings
Thanks guys. I’m open to ANY and ALL suggestions.
Chuck
I bought a clean ‘94 with 90k miles a few months ago. I had my credit card out and ready to order the BEGi S kit but I decided to first do the basic diagnostics…
Compression test was: 175, 165, 165, 170
Seemed good enough.
Vacuum was 18 in at idle.
Timing is 14* and I run 91 California crap gas. Runs good.
Then I did a leakdown test. The leakage was equally terrible in all four cylinders. The leakage past the rings was so bad, I could actually hear the oil gargling through the dipstick tube (with the oil filler cap in place).
I burn 1qt of 20w-50 dino per 300 miles and the oil turns jet-black within 50 miles. I’ve tried 6 or 7 different oils and weights with similar results.
I don’t think this motor qualifies for a turbo.
Power goal: If I had to state a power goal, I’d say 250whp. Doing it in steps would be fine.
Budget: If I had to state a budget, I’d say $7k.
If you’ve made it through this long post, thank you. My reason for posting is to get advice. I’m not quite sure what to do.
My original plan was to:
1) get bigger injectors, MSPNP and wideband installed. Sort out the timing and fuel.
2) then install the BEGi S kit.
3) then upgrade gradually.
But it looks like I need to rebuild/replace my motor first.
With my budget and hp goals, should I:
1) build a stout shortblock (forged pistons/rods) and port the head and extrude hone the intake? After machining and parts, that would be at least $3k, correct? Leaving me with $4k for other FI parts…
2) Or should I find a low mileage long block, leaving me with more cash for better FI parts?
3) Leave it as-is and boost it with crappy rings
Thanks guys. I’m open to ANY and ALL suggestions.
Chuck
#2
i was in the same boat as you, i bought a parts car with good motor and swapped the motor and tranny out. once i finish boosting it i will start a complete build on my old motor and once done swap back and turn up the boost
if you choose the rebuild route, leave the head alone for now and just rebuild the bottom yourself
CAT rods-$320 appx.
stock pistons ok at those levels so maybe just some high quality rings and call it a day
keep in mind you will need a strong clutch, like Clutchnet or ACT for those power levels, might as well do that first after the MS and WB and Injectors...
make sure to replace all seales when redoing your block, a new timing belt and WP would be a good idea as well
if you choose the rebuild route, leave the head alone for now and just rebuild the bottom yourself
CAT rods-$320 appx.
stock pistons ok at those levels so maybe just some high quality rings and call it a day
keep in mind you will need a strong clutch, like Clutchnet or ACT for those power levels, might as well do that first after the MS and WB and Injectors...
make sure to replace all seales when redoing your block, a new timing belt and WP would be a good idea as well
#4
Weird that the leakdown test was so bad and that much oil consumption with a pretty normal compression test. I'd have thought that the compression test would have been much lower.
Anyway, if 250hp is your target, then you don't "need" a built motor. It's always nice to have for the safety and headroom for more power later.
You can probably source a low-milage 1.8L with good compression for ~$500 and have more money left for other go fast parts, but the power bug is worse than crack so tough call.
If you can find a reasonable priced replacement engine, I say get that and swap it in to get your car turboed sooner (so you can enjoy...now!) and then rebuild your current engine on the side slowly for later when you want more. If you can't find a 1.8 engine in good shape for a decent price then you go built.
Anyway, if 250hp is your target, then you don't "need" a built motor. It's always nice to have for the safety and headroom for more power later.
You can probably source a low-milage 1.8L with good compression for ~$500 and have more money left for other go fast parts, but the power bug is worse than crack so tough call.
If you can find a reasonable priced replacement engine, I say get that and swap it in to get your car turboed sooner (so you can enjoy...now!) and then rebuild your current engine on the side slowly for later when you want more. If you can't find a 1.8 engine in good shape for a decent price then you go built.
#7
Search out a thread by "SamNavy" he had a build vs swap used motor discussion for his similar situation. I chose the "stout" route... never regretted it. With a 7k budget its well within your reach with some change to spare. Basic bottom end parts were something like 800-900 bucks (pistons/rods/gasket/ARP studs). Add in some machine work, and in the future you will be have that wonderful feeling of security, as opposed to the "oh **** it may blow" mindset
#9
Junior Member
Thread Starter
iTrader: (4)
Join Date: Oct 2007
Location: santa cruz
Posts: 245
Total Cats: 1
Great help guys. Thanks.
To those who asked, I think the reason my compression numbers were good despite the worn rings was due to carbon buildup. Looking through the spark plug holes, I see LOTS of carbon in all cylinders. And all the oil I'm burning probably compounds that issue.
To those who asked, I think the reason my compression numbers were good despite the worn rings was due to carbon buildup. Looking through the spark plug holes, I see LOTS of carbon in all cylinders. And all the oil I'm burning probably compounds that issue.
#15
I ran my talon for over 3 years with 115 compression and as much as 85% loss in the cylinders (some were worse than others). No problems. Only pulled the engine, because I picked up a miata to roll in while I tore the car apart. That kind of leak issue shouldn't result in engine loss, just power loss. Things will be a little less responsive, but the physical components should hold together all right.
#16
I have similar compression numbers but I haven't done a leakdown test yet. My car is currently undriveable with the exhaust manifold and downpipe pulled, waiting for my BEGi kit to arrive.
Could I do a leakdown test now, while I'm waiting for my kit to arrive?
Also, do leaks in the vacuum lines affect the leakdown test?
Could I do a leakdown test now, while I'm waiting for my kit to arrive?
Also, do leaks in the vacuum lines affect the leakdown test?
#20
Junior Member
Thread Starter
iTrader: (4)
Join Date: Oct 2007
Location: santa cruz
Posts: 245
Total Cats: 1
xveganxcowboyx and Brain,
It sounds like you guys both ran FI on motors that had serious sealing issues.
I assume blowby and oil consumption were bad?
Did those two factors make for a difficult tuning situation?
What does burning lots of oil do to the WB signal?
Thanks
It sounds like you guys both ran FI on motors that had serious sealing issues.
I assume blowby and oil consumption were bad?
Did those two factors make for a difficult tuning situation?
What does burning lots of oil do to the WB signal?
Thanks