cranks but won't start

Parley with regards to your 1987 to 1991 Bonneville, Olds 88, Olds 98 86-90 or Buick Le Sabre, Le Sabre T-Type and Park Avenue 85-90 . Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.
Post Reply
mimiddru
LE Member
Posts: 6
Joined: Fri Mar 11, 2016 2:53 pm
Year and Trim: 1991 le

cranks but won't start

Post by mimiddru »

1991 le overheated one night due to stuck thermostat. Front head gasket blew. Car still drove but sounded like a helicopter. I could feel air puffing out right by the exhaust manifold. Tried Blue Devil. No noticeable change. Added Lucas oil treatment, sprayed wd 40 in spark plug holes. Tried to start the car and it wouldn't turn over. Tried cranking by hand, and it does turn. Cranked by hand over and over, still won't turn over. Finally took off the head. Gasket was blown right where I could feel the air puffing out before. Had it resurfaced, replaced gasket. Still won't turn over. Still cranks by hand. Don't know where to go from here.
User avatar
MattStrike
Certified Bonneville Nut
Certified Bonneville Nut
Posts: 4760
Joined: Tue Aug 25, 2009 8:32 pm
Year and Trim: '99 Montana
'04 Dirtymax
'97 Camaro
'92 Trofeo
Location: SE Michigan

Re: cranks but won't start

Post by MattStrike »

Check the rear gasket too, any loss of compression will result in a hard starting situation. The other things to check is to make sure there is both spark and fuel. But most likely either the other gasket was also leaking, or you have cracked heads (the narrow part between the valves is the usual spot for cracking).
Boost addict
Image

The Fleet:
'93 SSEi - Twincharged + manual Build thread
'97 Camaro - Top swap
'05 STS - V8, AWD, her DD
'92 Trofeo - Fair weather DD
'99 Montana - top swap 3800
'04 Sierra 2500HD - LLY Duramax

Current project:
Something cool, trust me.

Upcoming projects:
'92 Bonneville SSE
'87 LeSabre T-type
'67 LeSabre

Gone to greener pastures:
'84 Sierra Classic - Twin turbo 3800
'97 LeSabre - Top swap

RIP:
'86 LeSabre - pictures
'93 SE - L67
mimiddru
LE Member
Posts: 6
Joined: Fri Mar 11, 2016 2:53 pm
Year and Trim: 1991 le

Re: cranks but won't start

Post by mimiddru »

Thanks for that. Actually, I got it started last night. Turns out I messed up the spark plug wiring (It happens. Lot to be said for being patient and well rested). Re-wired it properly and used starting fluid. It was running pretty well (no more helicopter sound from air puffing out) but started to peter out after a few miles. I'm gonna start by going back over everything and making sure I dotted my I's and crossed my T's. If there's still a problem, I'll do a compression test and depending, maybe try another head/block sealer. I heard there's this stuff called Liquid Glass that's cheap and works really well. Any other suggestions would be appreciated.
Post Reply