"Hydrolock" and Raw fuel smell (RESOLVED)
Thread Starter
Member


Joined: May 2015
Posts: 109
Likes: 7
Car: 1989 Chevy Camaro IROCZ
Engine: 355 TPI w/ EBL Flash
Transmission: 700R4
Axle/Gears: 2.77
"Hydrolock" and Raw fuel smell (RESOLVED)
It seems like this month is my1989 350 TPI, EBL-Flashed IROC's turn to be on this forum. Last week was because of a blown fusible link that I replaced and worked fine.
Now...
Possibly a bad fuel pressure regulator. Yesterday I got home from work fine till I came back 2 hours later.. The engine cranked over and then locked up after 3 or 4 turns. By this time there was a strong fuel smell. This morning the engine cranked over again and then stopped again. After reading here (Thank you thirdgen.org community!) I now suspect that the fuel pressure regulator diaphragm has ruptured and fuel is getting up into the plenum via the vacuum line, down the runners, and into the cylinders. Causing a "hydro-lock" symptom.
Till next time.
Now...
Possibly a bad fuel pressure regulator. Yesterday I got home from work fine till I came back 2 hours later.. The engine cranked over and then locked up after 3 or 4 turns. By this time there was a strong fuel smell. This morning the engine cranked over again and then stopped again. After reading here (Thank you thirdgen.org community!) I now suspect that the fuel pressure regulator diaphragm has ruptured and fuel is getting up into the plenum via the vacuum line, down the runners, and into the cylinders. Causing a "hydro-lock" symptom.
Till next time.
Last edited by IROC406; Aug 27, 2018 at 08:59 AM.
Joined: Oct 2001
Posts: 12,214
Likes: 1,140
From: Il
Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: "Hydrolock" and Raw fuel smell
Pull dipstick and check for fuel, also check the fuel psi regulator vac line for fuel. should be a simple fix. Good luck!
Joined: Sep 2003
Posts: 25,895
Likes: 429
From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: "Hydrolock" and Raw fuel smell
Yup easy to check. It will be very obvious
or injectors stuck open
or injectors stuck open
Thread Starter
Member


Joined: May 2015
Posts: 109
Likes: 7
Car: 1989 Chevy Camaro IROCZ
Engine: 355 TPI w/ EBL Flash
Transmission: 700R4
Axle/Gears: 2.77
Re: "Hydrolock" and Raw fuel smell
Thanks!
TTOP350 - "Pull dipstick and check for fuel, also check the fuel psi regulator vac line for fuel. should be a simple fix. Good luck!"
I did check the oil level and the smell of the oil on it this morning. Doesn't really smell like fuel. I think I will need another oil change. UGH I just did the oil change 2 weeks ago too.. It's about a half inch over the line but I don't know if it's because the oil settled afterwards or if fuel brought it up.
Orr89RocZ - "Yup easy to check. It will be very obvious or injectors stuck open"
I hope it's the regulator diaphragm!! I can afford a $75 regulator diaphragm instead of $280 set of injectors at the moment. With 180,000 miles it's senseless to change just one injector and with my 406 (or 434) build I am planning, I want to buy a set of 24lb injectors when I get the extra cash.
TTOP350 - "Pull dipstick and check for fuel, also check the fuel psi regulator vac line for fuel. should be a simple fix. Good luck!"
I did check the oil level and the smell of the oil on it this morning. Doesn't really smell like fuel. I think I will need another oil change. UGH I just did the oil change 2 weeks ago too.. It's about a half inch over the line but I don't know if it's because the oil settled afterwards or if fuel brought it up.
Orr89RocZ - "Yup easy to check. It will be very obvious or injectors stuck open"
I hope it's the regulator diaphragm!! I can afford a $75 regulator diaphragm instead of $280 set of injectors at the moment. With 180,000 miles it's senseless to change just one injector and with my 406 (or 434) build I am planning, I want to buy a set of 24lb injectors when I get the extra cash.
Joined: Sep 2003
Posts: 25,895
Likes: 429
From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: "Hydrolock" and Raw fuel smell
Depending on the hp goal you may need more than 24 for a 406
Thread Starter
Member


Joined: May 2015
Posts: 109
Likes: 7
Car: 1989 Chevy Camaro IROCZ
Engine: 355 TPI w/ EBL Flash
Transmission: 700R4
Axle/Gears: 2.77
Re: "Hydrolock" and Raw fuel smell
I plan on keeping my 2.77 BW gear so It's diesel-like torque that I want, not HP. Good vacuum and idle quality for everyday driving.
If I can keep a good rod length to crank stroke ratio I would like to see the 406 or 434 (debating) last me 180,000 miles like my 350 has. For my 406, I have the 5.7 rods and correct pistons for a 9.5 to 1 compression ratio. Heads will be AFR 195 or 210 with steam holes and intake will be FIRST performance TPI. The only two reasons I am looking at the 434 is because you can get them fully assembled and warranted around $3500. Also, I want roller cam and lifters without the retro-fit kit. I am skeptical about them based on the amount of people who's had problems with the T-bar links. Reliability is either good or bad with them and I already know nothing is like the stock style when it comes to reliability. Then there's the rocket block that would provide me an even better rod length to crank stroke ratio but the cost goes up with other components like the pan and timing cover set.
I have the 406 components already and may end up using it just because I don't have the extra funds just yet. Who knows what the future brings.
If I can keep a good rod length to crank stroke ratio I would like to see the 406 or 434 (debating) last me 180,000 miles like my 350 has. For my 406, I have the 5.7 rods and correct pistons for a 9.5 to 1 compression ratio. Heads will be AFR 195 or 210 with steam holes and intake will be FIRST performance TPI. The only two reasons I am looking at the 434 is because you can get them fully assembled and warranted around $3500. Also, I want roller cam and lifters without the retro-fit kit. I am skeptical about them based on the amount of people who's had problems with the T-bar links. Reliability is either good or bad with them and I already know nothing is like the stock style when it comes to reliability. Then there's the rocket block that would provide me an even better rod length to crank stroke ratio but the cost goes up with other components like the pan and timing cover set.
I have the 406 components already and may end up using it just because I don't have the extra funds just yet. Who knows what the future brings.
Joined: Sep 2003
Posts: 25,895
Likes: 429
From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: "Hydrolock" and Raw fuel smell
406 with 6” rod and good ring pack will last a long time. Dont go over 3.75” stroke imo, its not worth it for the small cube gain. A 415-420 on a 3.875 is doable but i still think a 400” is best. Torque is airflow so still need injector. 24 may get used up 30’s be better imo
Trending Topics
Thread Starter
Member


Joined: May 2015
Posts: 109
Likes: 7
Car: 1989 Chevy Camaro IROCZ
Engine: 355 TPI w/ EBL Flash
Transmission: 700R4
Axle/Gears: 2.77
Re: "Hydrolock" and Raw fuel smell
406 with 6” rod and good ring pack will last a long time. Dont go over 3.75” stroke imo, its not worth it for the small cube gain. A 415-420 on a 3.875 is doable but i still think a 400” is best. Torque is airflow so still need injector. 24 may get used up 30’s be better imo
Joined: Sep 2003
Posts: 25,895
Likes: 429
From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: "Hydrolock" and Raw fuel smell
Thanks for the heads up! I already have the 5.7" Scat rods and Keith Black pistons so 1.52 ratio is my only option now. I hope I will be content with a 3.75" stroke and hydraulic flat tappet. I see that the 30 pounders from southbay isn't that much more so with the EBL I should be ok
Thread Starter
Member


Joined: May 2015
Posts: 109
Likes: 7
Car: 1989 Chevy Camaro IROCZ
Engine: 355 TPI w/ EBL Flash
Transmission: 700R4
Axle/Gears: 2.77
Re: "Hydrolock" and Raw fuel smell
Thread Starter
Member


Joined: May 2015
Posts: 109
Likes: 7
Car: 1989 Chevy Camaro IROCZ
Engine: 355 TPI w/ EBL Flash
Transmission: 700R4
Axle/Gears: 2.77
Re: "Hydrolock" and Raw fuel smell
Definitely the fuel pressure regulator. I don't know how there wasn't a fire wow. Took off the vacuum line and directed it to a bottle. Key on and the flow of fuel in the bottle was nuts.
Joined: Sep 2003
Posts: 25,895
Likes: 429
From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: "Hydrolock" and Raw fuel smell
Lol good that you found the issue. I’ve been there before. Relatively easy fix
Thread Starter
Member


Joined: May 2015
Posts: 109
Likes: 7
Car: 1989 Chevy Camaro IROCZ
Engine: 355 TPI w/ EBL Flash
Transmission: 700R4
Axle/Gears: 2.77
Re: "Hydrolock" and Raw fuel smell
Definitely easy. 30 minutes tops. Problem now is that there may be fuel sitting on closed valves. I disconnected the coil wire and cranked it and other cylinders hydro locked. Once it cranks freely I will see if it starts up and then will change the oil.
Thread Starter
Member


Joined: May 2015
Posts: 109
Likes: 7
Car: 1989 Chevy Camaro IROCZ
Engine: 355 TPI w/ EBL Flash
Transmission: 700R4
Axle/Gears: 2.77
Re: "Hydrolock" and Raw fuel smell (RESOLVED)
All set now
I have been driving the car for two days. Runs much better. That regulator diaphragm must have been leaking fuel for quite a while because I had to hold that throttle a bit in order to start it after a period of time sitting. Now I can start it with no throttle assist. So, I did a new VE LEARN last night and what a difference. New found torque everywhere.especially when I am on the highway.
Thinking about the RAM AIR duct system now but that's on another thread.
Thanks Thirdgen.org community.
I have been driving the car for two days. Runs much better. That regulator diaphragm must have been leaking fuel for quite a while because I had to hold that throttle a bit in order to start it after a period of time sitting. Now I can start it with no throttle assist. So, I did a new VE LEARN last night and what a difference. New found torque everywhere.especially when I am on the highway.
Thinking about the RAM AIR duct system now but that's on another thread.
Thanks Thirdgen.org community.
Thread
Thread Starter
Forum
Replies
Last Post
JDIroc
Tech / General Engine
21
Dec 18, 2001 06:00 AM








